diff --git a/maxscale-system-test/mxs1506_no_master.cpp b/maxscale-system-test/mxs1506_no_master.cpp
index 3225a610f..7aec54cdd 100644
--- a/maxscale-system-test/mxs1506_no_master.cpp
+++ b/maxscale-system-test/mxs1506_no_master.cpp
@@ -19,7 +19,7 @@ bool query(TestConnections& test)
     sleep(5);
     Row row = get_row(test.maxscales->conn_rwsplit[0], "SELECT @a");
     test.maxscales->disconnect();
-    return row[0] == "1";
+    return !row.empty() && row[0] == "1";
 }
 
 void block(TestConnections& test, std::vector<int> nodes)
diff --git a/server/core/backend.cc b/server/core/backend.cc
index 298c474af..e92575519 100644
--- a/server/core/backend.cc
+++ b/server/core/backend.cc
@@ -179,6 +179,7 @@ void Backend::set_state(backend_state state)
 
 bool Backend::connect(MXS_SESSION* session, SessionCommandList* sescmd)
 {
+    ss_dassert(!in_use());
     bool rval = false;
 
     if ((m_dcb = dcb_connect(m_backend->server, session, m_backend->server->protocol)))
diff --git a/server/modules/routing/readwritesplit/rwsplit_select_backends.cc b/server/modules/routing/readwritesplit/rwsplit_select_backends.cc
index f33662d59..ee00be3ae 100644
--- a/server/modules/routing/readwritesplit/rwsplit_select_backends.cc
+++ b/server/modules/routing/readwritesplit/rwsplit_select_backends.cc
@@ -343,25 +343,36 @@ bool RWSplit::select_connect_backend_servers(MXS_SESSION *session,
     int slaves_connected = counts.second;
     int max_nslaves = max_slave_count();
 
-    ss_dassert(slaves_connected < max_nslaves || max_nslaves == 0);
+    ss_dassert(slaves_connected <= max_nslaves || max_nslaves == 0);
 
-    /** Connect to all possible slaves */
-    for (SRWBackend backend(get_slave_candidate(backends, master, cmpfun));
-         backend && slaves_connected < max_nslaves;
-         backend = get_slave_candidate(backends, master, cmpfun))
+    if (slaves_connected < max_nslaves)
     {
-        if (backend->can_connect() && backend->connect(session, sescmd_list))
+        /** Connect to all possible slaves */
+        for (SRWBackend backend(get_slave_candidate(backends, master, cmpfun));
+             backend && slaves_connected < max_nslaves;
+             backend = get_slave_candidate(backends, master, cmpfun))
         {
-            MXS_INFO("Selected Slave: %s", backend->name());
-
-            if (sescmd_list && sescmd_list->size() && expected_responses)
+            if (backend->can_connect() && backend->connect(session, sescmd_list))
             {
-                (*expected_responses)++;
-            }
+                MXS_INFO("Selected Slave: %s", backend->name());
 
-            slaves_connected++;
+                if (sescmd_list && sescmd_list->size() && expected_responses)
+                {
+                    (*expected_responses)++;
+                }
+
+                slaves_connected++;
+            }
         }
     }
+    else
+    {
+        /**
+         * We are already connected to all possible slaves. Currently this can
+         * only happen if this function is called by handle_error_new_connection
+         * and the routing of queued queries created new connections.
+         */
+    }
 
     return true;
 }
diff --git a/server/modules/routing/readwritesplit/rwsplitsession.cc b/server/modules/routing/readwritesplit/rwsplitsession.cc
index f7340cea8..7057f736a 100644
--- a/server/modules/routing/readwritesplit/rwsplitsession.cc
+++ b/server/modules/routing/readwritesplit/rwsplitsession.cc
@@ -681,6 +681,7 @@ void RWSplitSession::handleError(GWBUF *errmsgbuf, DCB *problem_dcb,
 
             if (m_current_master && m_current_master->in_use() && m_current_master == backend)
             {
+                MXS_INFO("Master '%s' failed", backend->name());
                 /** The connection to the master has failed */
 
                 if (!backend->is_waiting_result())
@@ -739,6 +740,7 @@ void RWSplitSession::handleError(GWBUF *errmsgbuf, DCB *problem_dcb,
             }
             else
             {
+                MXS_INFO("Slave '%s' failed", backend->name());
                 if (m_target_node && m_target_node == backend &&
                     session_trx_is_read_only(problem_dcb->session))
                 {