diff --git a/src/rx/rx.c b/src/rx/rx.c
index b3a6f5a26a..89e6df12d8 100644
--- a/src/rx/rx.c
+++ b/src/rx/rx.c
@@ -2994,11 +2994,6 @@ rxi_ReceivePacket(struct rx_packet *np, osi_socket socket,
 	return np;
     }
 
-    MUTEX_ENTER(&conn->conn_data_lock);
-    if (conn->maxSerial < np->header.serial)
-	conn->maxSerial = np->header.serial;
-    MUTEX_EXIT(&conn->conn_data_lock);
-
     /* If the connection is in an error state, send an abort packet and ignore
      * the incoming packet */
     if (conn->error) {
diff --git a/src/rx/rx.h b/src/rx/rx.h
index ec2a83343f..48e8e3ad7d 100644
--- a/src/rx/rx.h
+++ b/src/rx/rx.h
@@ -246,7 +246,6 @@ struct rx_connection {
                                        * call slot, or 0 if the slot is not busy */
     afs_uint32 serial;		/* Next outgoing packet serial number */
     afs_uint32 lastSerial;	/* # of last packet received, for computing skew */
-    afs_int32 maxSerial;	/* largest serial number seen on incoming packets */
     afs_int32 lastPacketSize; /* last >max attempt */
     afs_int32 lastPacketSizeSeq; /* seq number of attempt */
     afs_int32 lastPingSize; /* last MTU ping attempt */