diff --git a/game/server/ai_playerally.cpp b/game/server/ai_playerally.cpp
index 1f371fc9..4d6685ec 100644
--- a/game/server/ai_playerally.cpp
+++ b/game/server/ai_playerally.cpp
@@ -4,6 +4,8 @@
 //
 //=============================================================================//
 
+#undef sprintf
+
 #include "cbase.h"
 
 #include "sceneentity.h"