diff --git a/include/maxscale/protocol/mysql.h b/include/maxscale/protocol/mysql.h
index 438655eef..2dd77a44a 100644
--- a/include/maxscale/protocol/mysql.h
+++ b/include/maxscale/protocol/mysql.h
@@ -383,7 +383,7 @@ extern uint8_t null_client_sha1[MYSQL_SCRAMBLE_LEN];
 MYSQL_session* mysql_session_alloc();
 
 MySQLProtocol* mysql_protocol_init(DCB* dcb, int fd);
-void           mysql_protocol_done (DCB* dcb);
+bool           mysql_protocol_done (DCB* dcb);
 const char *gw_mysql_protocol_state2string(int state);
 int        mysql_send_com_quit(DCB* dcb, int packet_number, GWBUF* buf);
 GWBUF*     mysql_create_com_quit(GWBUF* bufparam, int packet_number);
diff --git a/server/modules/protocol/MySQL/MySQLClient/mysql_client.c b/server/modules/protocol/MySQL/MySQLClient/mysql_client.c
index 304c8d47b..e1fd3e802 100644
--- a/server/modules/protocol/MySQL/MySQLClient/mysql_client.c
+++ b/server/modules/protocol/MySQL/MySQLClient/mysql_client.c
@@ -1295,11 +1295,22 @@ static int gw_client_close(DCB *dcb)
 {
     CHK_DCB(dcb);
     ss_dassert(dcb->protocol);
-    mysql_protocol_done(dcb);
-    MXS_SESSION* target = dcb->session;
-    ss_debug(MXS_SESSION* removed = ) mxs_worker_deregister_session(target->ses_id);
-    ss_dassert(removed == target);
-    session_close(target);
+
+    if (mysql_protocol_done(dcb))
+    {
+        MXS_SESSION* target = dcb->session;
+
+        if (target->state != SESSION_STATE_TO_BE_FREED &&
+            target->state != SESSION_STATE_DUMMY)
+        {
+            ss_dassert(target->state == SESSION_STATE_ROUTER_READY ||
+                       target->state == SESSION_STATE_STOPPING);
+            ss_debug(MXS_SESSION* removed =) mxs_worker_deregister_session(target->ses_id);
+            ss_dassert(removed == target);
+            session_close(target);
+        }
+    }
+
     return 1;
 }
 
diff --git a/server/modules/protocol/MySQL/mysql_common.c b/server/modules/protocol/MySQL/mysql_common.c
index 5e592f6d3..d593ed6a5 100644
--- a/server/modules/protocol/MySQL/mysql_common.c
+++ b/server/modules/protocol/MySQL/mysql_common.c
@@ -120,36 +120,35 @@ return_p:
 }
 
 /**
- * mysql_protocol_done
+ * Free protocol object
  *
- * free protocol allocations.
- *
- * @param dcb owner DCB
+ * @param dcb Owner DCB
  *
+ * @return True if protocol was closed
  */
-void mysql_protocol_done(DCB* dcb)
+bool mysql_protocol_done(DCB* dcb)
 {
-    MySQLProtocol* p;
-    server_command_t* scmd;
-    server_command_t* scmd2;
-
-    p = (MySQLProtocol *)dcb->protocol;
+    bool rval = false;
+    MySQLProtocol* p = (MySQLProtocol *)dcb->protocol;
 
     if (p->protocol_state == MYSQL_PROTOCOL_ACTIVE)
     {
-        scmd = p->protocol_cmd_history;
+        server_command_t* scmd = p->protocol_cmd_history;
 
-        while (scmd != NULL)
+        while (scmd)
         {
-            scmd2 = scmd->scom_next;
-            MXS_FREE(scmd);
-            scmd = scmd2;
+            server_command_t* temp = scmd;
+            scmd = scmd->scom_next;
+            MXS_FREE(temp);
         }
 
         gwbuf_free(p->stored_query);
 
         p->protocol_state = MYSQL_PROTOCOL_DONE;
+        rval = true;
     }
+
+    return rval;
 }
 
 /**