diff --git a/jetty-client/src/main/java/org/eclipse/jetty/client/HttpRequest.java b/jetty-client/src/main/java/org/eclipse/jetty/client/HttpRequest.java
index 2dd02292c5c..79f75048025 100644
--- a/jetty-client/src/main/java/org/eclipse/jetty/client/HttpRequest.java
+++ b/jetty-client/src/main/java/org/eclipse/jetty/client/HttpRequest.java
@@ -666,13 +666,24 @@ public class HttpRequest implements Request
     @Override
     public void send(Response.CompleteListener listener)
     {
-        if (getTimeout() > 0)
+        TimeoutCompleteListener timeoutListener = null;
+        try
         {
-            TimeoutCompleteListener timeoutListener = new TimeoutCompleteListener(this);
-            timeoutListener.schedule(client.getScheduler());
-            responseListeners.add(timeoutListener);
+            if (getTimeout() > 0)
+            {
+                timeoutListener = new TimeoutCompleteListener(this);
+                timeoutListener.schedule(client.getScheduler());
+                responseListeners.add(timeoutListener);
+            }
+            send(this, listener);
+        }
+        catch (Throwable x)
+        {
+            // Do not leak the scheduler task if we
+            // can't even start sending the request.
+            if (timeoutListener != null)
+                timeoutListener.cancel();
         }
-        send(this, listener);
     }
 
     private void send(HttpRequest request, Response.CompleteListener listener)
diff --git a/jetty-client/src/main/java/org/eclipse/jetty/client/TimeoutCompleteListener.java b/jetty-client/src/main/java/org/eclipse/jetty/client/TimeoutCompleteListener.java
index 00f2de78978..45b9a8178be 100644
--- a/jetty-client/src/main/java/org/eclipse/jetty/client/TimeoutCompleteListener.java
+++ b/jetty-client/src/main/java/org/eclipse/jetty/client/TimeoutCompleteListener.java
@@ -44,21 +44,20 @@ public class TimeoutCompleteListener implements Response.CompleteListener, Runna
     @Override
     public void onComplete(Result result)
     {
-        Scheduler.Task task = this.task.getAndSet(null);
-        if (task != null)
-        {
-            boolean cancelled = task.cancel();
-            if (LOG.isDebugEnabled())
-                LOG.debug("Cancelled (successfully: {}) timeout task {}", cancelled, task);
-        }
+        cancel();
     }
 
     public boolean schedule(Scheduler scheduler)
     {
         long timeout = request.getTimeout();
         Scheduler.Task task = scheduler.schedule(this, timeout, TimeUnit.MILLISECONDS);
-        if (this.task.getAndSet(task) != null)
+        Scheduler.Task existing = this.task.getAndSet(task);
+        if (existing != null)
+        {
+            existing.cancel();
+            cancel();
             throw new IllegalStateException();
+        }
         if (LOG.isDebugEnabled())
             LOG.debug("Scheduled timeout task {} in {} ms for {}", task, timeout, request);
         return true;
@@ -71,4 +70,15 @@ public class TimeoutCompleteListener implements Response.CompleteListener, Runna
             LOG.debug("Executing timeout task {} for {}", task, request);
         request.abort(new TimeoutException("Total timeout elapsed"));
     }
+
+    public void cancel()
+    {
+        Scheduler.Task task = this.task.getAndSet(null);
+        if (task != null)
+        {
+            boolean cancelled = task.cancel();
+            if (LOG.isDebugEnabled())
+                LOG.debug("Cancelled (successfully: {}) timeout task {}", cancelled, task);
+        }
+    }
 }
diff --git a/jetty-client/src/test/java/org/eclipse/jetty/client/HttpClientTimeoutTest.java b/jetty-client/src/test/java/org/eclipse/jetty/client/HttpClientTimeoutTest.java
index df347c4bc5f..971ebf75b7d 100644
--- a/jetty-client/src/test/java/org/eclipse/jetty/client/HttpClientTimeoutTest.java
+++ b/jetty-client/src/test/java/org/eclipse/jetty/client/HttpClientTimeoutTest.java
@@ -428,6 +428,28 @@ public class HttpClientTimeoutTest extends AbstractHttpClientServerTest
         Assert.assertTrue(latch.await(5, TimeUnit.SECONDS));
     }
 
+    @Test
+    public void testTimeoutCancelledWhenSendingThrowsException() throws Exception
+    {
+        start(new EmptyServerHandler());
+
+        long timeout = 1000;
+        Request request = client.newRequest("bad_scheme://localhost:" + connector.getLocalPort());
+        request.timeout(timeout, TimeUnit.MILLISECONDS)
+                .send(new Response.CompleteListener()
+                {
+                    @Override
+                    public void onComplete(Result result)
+                    {
+                    }
+                });
+
+        Thread.sleep(2 * timeout);
+
+        // If the task was not cancelled, it aborted the request.
+        Assert.assertNull(request.getAbortCause());
+    }
+
     private void assumeConnectTimeout(String host, int port, int connectTimeout) throws IOException
     {
         try (Socket socket = new Socket())