diff --git a/src/d_net.c b/src/d_net.c
index 98fe71ab8..70cdc5f14 100644
--- a/src/d_net.c
+++ b/src/d_net.c
@@ -716,7 +716,7 @@ void Net_CloseConnection(INT32 node)
 	if (!node)
 		return;
 
-	if (node >= MAXNETNODES) // prevent invalid nodes from crashing the game
+	if (node < 0 || node >= MAXNETNODES) // prevent invalid nodes from crashing the game
 	{
 		CONS_Alert(CONS_WARNING, M_GetText("Net_CloseConnection: invalid node %d detected!\n"), node);
 		return;