diff --git a/quiche/quic/core/quic_ping_manager.cc b/quiche/quic/core/quic_ping_manager.cc
index 7ce158d..e3947e5 100644
--- a/quiche/quic/core/quic_ping_manager.cc
+++ b/quiche/quic/core/quic_ping_manager.cc
@@ -136,7 +136,11 @@
     // Alarm is set to an earlier time. Do not postpone it.
     QUIC_BUG_IF(quic_retransmittable_on_wire_deadline_is_in_past,
                 retransmittable_on_wire_deadline_ < now)
-        << "QUIC retransmittable PING deadline is in past";
+        << "QUIC retransmittable PING deadline is in past, now: "
+        << now.ToDebuggingValue() << ", retransmittable_on_wire_deadline: "
+        << retransmittable_on_wire_deadline_.ToDebuggingValue()
+        << ", difference: "
+        << (now - retransmittable_on_wire_deadline_).ToDebuggingValue();
     return;
   }
   retransmittable_on_wire_deadline_ = now + retransmittable_on_wire_timeout;