diff --git a/hardware/lm4f/libraries/Ethernet/EthernetClient.cpp b/hardware/lm4f/libraries/Ethernet/EthernetClient.cpp
index 6e3b79c5cd8..02fd9b1a39d 100644
--- a/hardware/lm4f/libraries/Ethernet/EthernetClient.cpp
+++ b/hardware/lm4f/libraries/Ethernet/EthernetClient.cpp
@@ -192,6 +192,9 @@ int EthernetClient::connect(IPAddress ip, uint16_t port, unsigned long timeout)
 
 	if (cs->cpcb->state != ESTABLISHED) {
 		_connected = false;
+		tcp_close((tcp_pcb*)cs->cpcb);
+		cs->cpcb = NULL;
+		return false;
 	}
 
 	/* Poll to determine if the peer is still alive */