diff --git a/p2p/base/port.cc b/p2p/base/port.cc
index 035d3d4bb3..7b54c11cb8 100644
--- a/p2p/base/port.cc
+++ b/p2p/base/port.cc
@@ -188,6 +188,9 @@ void Port::Construct() {
 }
 
 Port::~Port() {
+  RTC_DCHECK_RUN_ON(thread_);
+  CancelPendingTasks();
+
   // Delete all of the remaining connections.  We copy the list up front
   // because each deletion will cause it to be modified.
 
@@ -609,6 +612,16 @@ rtc::DiffServCodePoint Port::StunDscpValue() const {
   return rtc::DSCP_NO_CHANGE;
 }
 
+void Port::set_timeout_delay(int delay) {
+  RTC_DCHECK_RUN_ON(thread_);
+  // Although this method is meant to only be used by tests, some downstream
+  // projects have started using it. Ideally we should update our tests to not
+  // require to modify this state and instead use a testing harness that allows
+  // adjusting the clock and then just use the kPortTimeoutDelay constant
+  // directly.
+  timeout_delay_ = delay;
+}
+
 bool Port::ParseStunUsername(const StunMessage* stun_msg,
                              std::string* local_ufrag,
                              std::string* remote_ufrag) const {
@@ -818,7 +831,14 @@ void Port::Prune() {
   thread_->Post(RTC_FROM_HERE, this, MSG_DESTROY_IF_DEAD);
 }
 
+// Call to stop any currently pending operations from running.
+void Port::CancelPendingTasks() {
+  RTC_DCHECK_RUN_ON(thread_);
+  thread_->Clear(this);
+}
+
 void Port::OnMessage(rtc::Message* pmsg) {
+  RTC_DCHECK_RUN_ON(thread_);
   RTC_DCHECK(pmsg->message_id == MSG_DESTROY_IF_DEAD);
   bool dead =
       (state_ == State::INIT || state_ == State::PRUNED) &&
diff --git a/p2p/base/port.h b/p2p/base/port.h
index 1e20d13462..43196e5c03 100644
--- a/p2p/base/port.h
+++ b/p2p/base/port.h
@@ -160,7 +160,7 @@ typedef std::set<rtc::SocketAddress> ServerAddresses;
 // connections to similar mechanisms of the other client.  Subclasses of this
 // one add support for specific mechanisms like local UDP ports.
 class Port : public PortInterface,
-             public rtc::MessageHandlerAutoCleanup,
+             public rtc::MessageHandler,
              public sigslot::has_slots<> {
  public:
   // INIT: The state when a port is just created.
@@ -209,6 +209,9 @@ class Port : public PortInterface,
   // Allows a port to be destroyed if no connection is using it.
   void Prune();
 
+  // Call to stop any currently pending operations from running.
+  void CancelPendingTasks();
+
   // The thread on which this port performs its I/O.
   rtc::Thread* thread() { return thread_; }
 
@@ -322,7 +325,7 @@ class Port : public PortInterface,
   uint16_t max_port() { return max_port_; }
 
   // Timeout shortening function to speed up unit tests.
-  void set_timeout_delay(int delay) { timeout_delay_ = delay; }
+  void set_timeout_delay(int delay);
 
   // This method will return local and remote username fragements from the
   // stun username attribute if present.
@@ -437,7 +440,7 @@ class Port : public PortInterface,
 
   void OnNetworkTypeChanged(const rtc::Network* network);
 
-  rtc::Thread* thread_;
+  rtc::Thread* const thread_;
   rtc::PacketSocketFactory* factory_;
   std::string type_;
   bool send_retransmit_count_attribute_;