diff --git a/google-cloud-spanner/src/main/java/com/google/cloud/spanner/AbstractReadContext.java b/google-cloud-spanner/src/main/java/com/google/cloud/spanner/AbstractReadContext.java
index ae18a1e4f5f..27b6440ab9b 100644
--- a/google-cloud-spanner/src/main/java/com/google/cloud/spanner/AbstractReadContext.java
+++ b/google-cloud-spanner/src/main/java/com/google/cloud/spanner/AbstractReadContext.java
@@ -451,11 +451,6 @@ void initTransaction() {
     this.tracer = builder.tracer;
   }
 
-  @Override
-  public void setSpan(ISpan span) {
-    this.span = span;
-  }
-
   long getSeqNo() {
     return seqNo.incrementAndGet();
   }
diff --git a/google-cloud-spanner/src/main/java/com/google/cloud/spanner/AsyncTransactionManagerImpl.java b/google-cloud-spanner/src/main/java/com/google/cloud/spanner/AsyncTransactionManagerImpl.java
index 8b20dd824a0..cd83b247518 100644
--- a/google-cloud-spanner/src/main/java/com/google/cloud/spanner/AsyncTransactionManagerImpl.java
+++ b/google-cloud-spanner/src/main/java/com/google/cloud/spanner/AsyncTransactionManagerImpl.java
@@ -47,11 +47,6 @@ final class AsyncTransactionManagerImpl
     this.options = Options.fromTransactionOptions(options);
   }
 
-  @Override
-  public void setSpan(ISpan span) {
-    this.span = span;
-  }
-
   @Override
   public void close() {
     closeAsync();
diff --git a/google-cloud-spanner/src/main/java/com/google/cloud/spanner/DatabaseClientImpl.java b/google-cloud-spanner/src/main/java/com/google/cloud/spanner/DatabaseClientImpl.java
index e9c9818f451..0dab9639c74 100644
--- a/google-cloud-spanner/src/main/java/com/google/cloud/spanner/DatabaseClientImpl.java
+++ b/google-cloud-spanner/src/main/java/com/google/cloud/spanner/DatabaseClientImpl.java
@@ -21,6 +21,7 @@
 import com.google.cloud.spanner.Options.TransactionOption;
 import com.google.cloud.spanner.Options.UpdateOption;
 import com.google.cloud.spanner.SessionPool.PooledSessionFuture;
+import com.google.cloud.spanner.SessionPool.SessionFuture;
 import com.google.cloud.spanner.SpannerImpl.ClosedException;
 import com.google.common.annotations.VisibleForTesting;
 import com.google.common.base.Function;
@@ -52,6 +53,10 @@ PooledSessionFuture getSession() {
     return pool.getSession();
   }
 
+  SessionFuture getMultiplexedSession() {
+    return pool.getMultiplexedSessionWithFallback();
+  }
+
   @Override
   public Dialect getDialect() {
     return pool.getDialect();
@@ -123,7 +128,7 @@ public ServerStream<BatchWriteResponse> batchWriteAtLeastOnce(
   public ReadContext singleUse() {
     ISpan span = tracer.spanBuilder(READ_ONLY_TRANSACTION);
     try (IScope s = tracer.withSpan(span)) {
-      return getSession().singleUse();
+      return getMultiplexedSession().singleUse();
     } catch (RuntimeException e) {
       span.setStatus(e);
       span.end();
@@ -135,7 +140,7 @@ public ReadContext singleUse() {
   public ReadContext singleUse(TimestampBound bound) {
     ISpan span = tracer.spanBuilder(READ_ONLY_TRANSACTION);
     try (IScope s = tracer.withSpan(span)) {
-      return getSession().singleUse(bound);
+      return getMultiplexedSession().singleUse(bound);
     } catch (RuntimeException e) {
       span.setStatus(e);
       span.end();
@@ -147,7 +152,7 @@ public ReadContext singleUse(TimestampBound bound) {
   public ReadOnlyTransaction singleUseReadOnlyTransaction() {
     ISpan span = tracer.spanBuilder(READ_ONLY_TRANSACTION);
     try (IScope s = tracer.withSpan(span)) {
-      return getSession().singleUseReadOnlyTransaction();
+      return getMultiplexedSession().singleUseReadOnlyTransaction();
     } catch (RuntimeException e) {
       span.setStatus(e);
       span.end();
@@ -159,7 +164,7 @@ public ReadOnlyTransaction singleUseReadOnlyTransaction() {
   public ReadOnlyTransaction singleUseReadOnlyTransaction(TimestampBound bound) {
     ISpan span = tracer.spanBuilder(READ_ONLY_TRANSACTION);
     try (IScope s = tracer.withSpan(span)) {
-      return getSession().singleUseReadOnlyTransaction(bound);
+      return getMultiplexedSession().singleUseReadOnlyTransaction(bound);
     } catch (RuntimeException e) {
       span.setStatus(e);
       span.end();
@@ -171,7 +176,7 @@ public ReadOnlyTransaction singleUseReadOnlyTransaction(TimestampBound bound) {
   public ReadOnlyTransaction readOnlyTransaction() {
     ISpan span = tracer.spanBuilder(READ_ONLY_TRANSACTION);
     try (IScope s = tracer.withSpan(span)) {
-      return getSession().readOnlyTransaction();
+      return getMultiplexedSession().readOnlyTransaction();
     } catch (RuntimeException e) {
       span.setStatus(e);
       span.end();
@@ -183,7 +188,7 @@ public ReadOnlyTransaction readOnlyTransaction() {
   public ReadOnlyTransaction readOnlyTransaction(TimestampBound bound) {
     ISpan span = tracer.spanBuilder(READ_ONLY_TRANSACTION);
     try (IScope s = tracer.withSpan(span)) {
-      return getSession().readOnlyTransaction(bound);
+      return getMultiplexedSession().readOnlyTransaction(bound);
     } catch (RuntimeException e) {
       span.setStatus(e);
       span.end();
diff --git a/google-cloud-spanner/src/main/java/com/google/cloud/spanner/PartitionedDmlTransaction.java b/google-cloud-spanner/src/main/java/com/google/cloud/spanner/PartitionedDmlTransaction.java
index d498bb232a1..2b1be0ad9cd 100644
--- a/google-cloud-spanner/src/main/java/com/google/cloud/spanner/PartitionedDmlTransaction.java
+++ b/google-cloud-spanner/src/main/java/com/google/cloud/spanner/PartitionedDmlTransaction.java
@@ -138,10 +138,6 @@ public void invalidate() {
     isValid = false;
   }
 
-  /** No-op method needed to implement SessionTransaction interface. */
-  @Override
-  public void setSpan(ISpan span) {}
-
   private Duration tryUpdateTimeout(final Duration timeout, final Stopwatch stopwatch) {
     final Duration remainingTimeout =
         timeout.minus(stopwatch.elapsed(TimeUnit.MILLISECONDS), ChronoUnit.MILLIS);
diff --git a/google-cloud-spanner/src/main/java/com/google/cloud/spanner/SessionImpl.java b/google-cloud-spanner/src/main/java/com/google/cloud/spanner/SessionImpl.java
index 8c4a0068599..be2e7ff30b2 100644
--- a/google-cloud-spanner/src/main/java/com/google/cloud/spanner/SessionImpl.java
+++ b/google-cloud-spanner/src/main/java/com/google/cloud/spanner/SessionImpl.java
@@ -91,9 +91,6 @@ interface SessionTransaction {
 
     /** Invalidates the transaction, generally because a new one has been started on the session. */
     void invalidate();
-
-    /** Registers the current span on the transaction. */
-    void setSpan(ISpan span);
   }
 
   private final SpannerImpl spanner;
@@ -105,7 +102,6 @@ interface SessionTransaction {
   private volatile Instant lastUseTime;
   @Nullable private final Instant createTime;
   private final boolean isMultiplexed;
-  private ISpan currentSpan;
 
   SessionImpl(SpannerImpl spanner, String name, Map<SpannerRpc.Option, ?> options) {
     this.spanner = spanner;
@@ -143,14 +139,6 @@ public String getName() {
     return options;
   }
 
-  void setCurrentSpan(ISpan span) {
-    currentSpan = span;
-  }
-
-  ISpan getCurrentSpan() {
-    return currentSpan;
-  }
-
   Instant getLastUseTime() {
     return lastUseTime;
   }
@@ -308,7 +296,7 @@ public ReadContext singleUse(TimestampBound bound) {
             .setDefaultPrefetchChunks(spanner.getDefaultPrefetchChunks())
             .setDefaultDecodeMode(spanner.getDefaultDecodeMode())
             .setDefaultDirectedReadOptions(spanner.getOptions().getDirectedReadOptions())
-            .setSpan(currentSpan)
+            .setSpan(tracer.getCurrentSpan())
             .setTracer(tracer)
             .setExecutorProvider(spanner.getAsyncExecutorProvider())
             .build());
@@ -330,7 +318,7 @@ public ReadOnlyTransaction singleUseReadOnlyTransaction(TimestampBound bound) {
             .setDefaultPrefetchChunks(spanner.getDefaultPrefetchChunks())
             .setDefaultDecodeMode(spanner.getDefaultDecodeMode())
             .setDefaultDirectedReadOptions(spanner.getOptions().getDirectedReadOptions())
-            .setSpan(currentSpan)
+            .setSpan(tracer.getCurrentSpan())
             .setTracer(tracer)
             .setExecutorProvider(spanner.getAsyncExecutorProvider())
             .buildSingleUseReadOnlyTransaction());
@@ -352,7 +340,7 @@ public ReadOnlyTransaction readOnlyTransaction(TimestampBound bound) {
             .setDefaultPrefetchChunks(spanner.getDefaultPrefetchChunks())
             .setDefaultDecodeMode(spanner.getDefaultDecodeMode())
             .setDefaultDirectedReadOptions(spanner.getOptions().getDirectedReadOptions())
-            .setSpan(currentSpan)
+            .setSpan(tracer.getCurrentSpan())
             .setTracer(tracer)
             .setExecutorProvider(spanner.getAsyncExecutorProvider())
             .build());
@@ -370,12 +358,12 @@ public AsyncRunner runAsync(TransactionOption... options) {
 
   @Override
   public TransactionManager transactionManager(TransactionOption... options) {
-    return new TransactionManagerImpl(this, currentSpan, tracer, options);
+    return new TransactionManagerImpl(this, tracer.getCurrentSpan(), tracer, options);
   }
 
   @Override
   public AsyncTransactionManagerImpl transactionManagerAsync(TransactionOption... options) {
-    return new AsyncTransactionManagerImpl(this, currentSpan, options);
+    return new AsyncTransactionManagerImpl(this, tracer.getCurrentSpan(), options);
   }
 
   @Override
@@ -470,7 +458,7 @@ TransactionContextImpl newTransaction(Options options) {
         .setDefaultQueryOptions(spanner.getDefaultQueryOptions(databaseId))
         .setDefaultPrefetchChunks(spanner.getDefaultPrefetchChunks())
         .setDefaultDecodeMode(spanner.getDefaultDecodeMode())
-        .setSpan(currentSpan)
+        .setSpan(tracer.getCurrentSpan())
         .setTracer(tracer)
         .setExecutorProvider(spanner.getAsyncExecutorProvider())
         .setClock(poolMaintainerClock == null ? new Clock() : poolMaintainerClock)
@@ -479,14 +467,12 @@ TransactionContextImpl newTransaction(Options options) {
 
   <T extends SessionTransaction> T setActive(@Nullable T ctx) {
     throwIfTransactionsPending();
-
-    if (activeTransaction != null) {
-      activeTransaction.invalidate();
-    }
-    activeTransaction = ctx;
-    readyTransactionId = null;
-    if (activeTransaction != null) {
-      activeTransaction.setSpan(currentSpan);
+    if (!this.isMultiplexed) {
+      if (activeTransaction != null) {
+        activeTransaction.invalidate();
+      }
+      activeTransaction = ctx;
+      readyTransactionId = null;
     }
     return ctx;
   }
diff --git a/google-cloud-spanner/src/main/java/com/google/cloud/spanner/SessionPool.java b/google-cloud-spanner/src/main/java/com/google/cloud/spanner/SessionPool.java
index a5eee9d0db7..ba0d17b2690 100644
--- a/google-cloud-spanner/src/main/java/com/google/cloud/spanner/SessionPool.java
+++ b/google-cloud-spanner/src/main/java/com/google/cloud/spanner/SessionPool.java
@@ -1908,15 +1908,11 @@ public void prepareReadWriteTransaction() {
 
     private void keepAlive() {
       markUsed();
-      final ISpan previousSpan = delegate.getCurrentSpan();
-      delegate.setCurrentSpan(tracer.getBlankSpan());
       try (ResultSet resultSet =
           delegate
               .singleUse(TimestampBound.ofMaxStaleness(60, TimeUnit.SECONDS))
               .executeQuery(Statement.newBuilder("SELECT 1").build())) {
         resultSet.next();
-      } finally {
-        delegate.setCurrentSpan(previousSpan);
       }
     }
 
@@ -1955,7 +1951,6 @@ public SessionImpl getDelegate() {
 
     @Override
     public void markBusy(ISpan span) {
-      this.delegate.setCurrentSpan(span);
       this.state = SessionState.BUSY;
     }
 
diff --git a/google-cloud-spanner/src/main/java/com/google/cloud/spanner/TransactionManagerImpl.java b/google-cloud-spanner/src/main/java/com/google/cloud/spanner/TransactionManagerImpl.java
index 95ffd1168b2..9e245148e61 100644
--- a/google-cloud-spanner/src/main/java/com/google/cloud/spanner/TransactionManagerImpl.java
+++ b/google-cloud-spanner/src/main/java/com/google/cloud/spanner/TransactionManagerImpl.java
@@ -40,15 +40,6 @@ final class TransactionManagerImpl implements TransactionManager, SessionTransac
     this.options = Options.fromTransactionOptions(options);
   }
 
-  ISpan getSpan() {
-    return span;
-  }
-
-  @Override
-  public void setSpan(ISpan span) {
-    this.span = span;
-  }
-
   @Override
   public TransactionContext begin() {
     Preconditions.checkState(txn == null, "begin can only be called once");
diff --git a/google-cloud-spanner/src/main/java/com/google/cloud/spanner/TransactionRunnerImpl.java b/google-cloud-spanner/src/main/java/com/google/cloud/spanner/TransactionRunnerImpl.java
index 370d2f662f5..e1021b81046 100644
--- a/google-cloud-spanner/src/main/java/com/google/cloud/spanner/TransactionRunnerImpl.java
+++ b/google-cloud-spanner/src/main/java/com/google/cloud/spanner/TransactionRunnerImpl.java
@@ -985,11 +985,7 @@ public TransactionRunner allowNestedTransaction() {
     this.options = Options.fromTransactionOptions(options);
     this.txn = session.newTransaction(this.options);
     this.tracer = session.getTracer();
-  }
-
-  @Override
-  public void setSpan(ISpan span) {
-    this.span = span;
+    this.span = tracer.getCurrentSpan();
   }
 
   @Nullable
diff --git a/google-cloud-spanner/src/test/java/com/google/cloud/spanner/SessionImplTest.java b/google-cloud-spanner/src/test/java/com/google/cloud/spanner/SessionImplTest.java
index ff50bf52e70..fbd5c5d020e 100644
--- a/google-cloud-spanner/src/test/java/com/google/cloud/spanner/SessionImplTest.java
+++ b/google-cloud-spanner/src/test/java/com/google/cloud/spanner/SessionImplTest.java
@@ -140,7 +140,6 @@ public void setUp() {
     Span oTspan = mock(Span.class);
     ISpan span = new OpenTelemetrySpan(oTspan);
     when(oTspan.makeCurrent()).thenReturn(mock(Scope.class));
-    ((SessionImpl) session).setCurrentSpan(span);
     // We expect the same options, "options", on all calls on "session".
     options = optionsCaptor.getValue();
   }
diff --git a/google-cloud-spanner/src/test/java/com/google/cloud/spanner/SessionPoolTest.java b/google-cloud-spanner/src/test/java/com/google/cloud/spanner/SessionPoolTest.java
index e1c295c14de..da6fae3faab 100644
--- a/google-cloud-spanner/src/test/java/com/google/cloud/spanner/SessionPoolTest.java
+++ b/google-cloud-spanner/src/test/java/com/google/cloud/spanner/SessionPoolTest.java
@@ -1455,7 +1455,6 @@ public void testSessionNotFoundReadWriteTransaction() {
       when(closedSession.beginTransactionAsync(any(), eq(true))).thenThrow(sessionNotFound);
       when(closedSession.getTracer()).thenReturn(tracer);
       TransactionRunnerImpl closedTransactionRunner = new TransactionRunnerImpl(closedSession);
-      closedTransactionRunner.setSpan(span);
       when(closedSession.readWriteTransaction()).thenReturn(closedTransactionRunner);
 
       final SessionImpl openSession = mock(SessionImpl.class);
@@ -1470,7 +1469,6 @@ public void testSessionNotFoundReadWriteTransaction() {
           .thenReturn(ApiFutures.immediateFuture(ByteString.copyFromUtf8("open-txn")));
       when(openSession.getTracer()).thenReturn(tracer);
       TransactionRunnerImpl openTransactionRunner = new TransactionRunnerImpl(openSession);
-      openTransactionRunner.setSpan(span);
       when(openSession.readWriteTransaction()).thenReturn(openTransactionRunner);
 
       ResultSet openResultSet = mock(ResultSet.class);
diff --git a/google-cloud-spanner/src/test/java/com/google/cloud/spanner/TransactionRunnerImplTest.java b/google-cloud-spanner/src/test/java/com/google/cloud/spanner/TransactionRunnerImplTest.java
index cf5f901f65e..ff0a6921450 100644
--- a/google-cloud-spanner/src/test/java/com/google/cloud/spanner/TransactionRunnerImplTest.java
+++ b/google-cloud-spanner/src/test/java/com/google/cloud/spanner/TransactionRunnerImplTest.java
@@ -146,7 +146,6 @@ public void setUp() {
     Span oTspan = mock(Span.class);
     span = new OpenTelemetrySpan(oTspan);
     when(oTspan.makeCurrent()).thenReturn(mock(Scope.class));
-    transactionRunner.setSpan(span);
   }
 
   @SuppressWarnings("unchecked")
@@ -312,9 +311,7 @@ public void prepareReadWriteTransaction() {
             throw new IllegalStateException();
           }
         };
-    session.setCurrentSpan(new OpenTelemetrySpan(mock(io.opentelemetry.api.trace.Span.class)));
     TransactionRunnerImpl runner = new TransactionRunnerImpl(session);
-    runner.setSpan(span);
     assertThat(usedInlinedBegin).isFalse();
     runner.run(
         transaction -> {
@@ -347,7 +344,6 @@ private long[] batchDmlException(int status) {
             ApiFutures.immediateFuture(ByteString.copyFromUtf8(UUID.randomUUID().toString())));
     when(session.getName()).thenReturn(SessionId.of("p", "i", "d", "test").getName());
     TransactionRunnerImpl runner = new TransactionRunnerImpl(session);
-    runner.setSpan(span);
     ExecuteBatchDmlResponse response1 =
         ExecuteBatchDmlResponse.newBuilder()
             .addResultSets(