diff --git a/src/lua_infolib.c b/src/lua_infolib.c
index eeb1067a3..67b9fb82d 100644
--- a/src/lua_infolib.c
+++ b/src/lua_infolib.c
@@ -242,17 +242,12 @@ static int lib_getSpriteInfo(lua_State *L)
 	UINT32 i = NUMSPRITES;
 	lua_remove(L, 1);
 
-	if (lua_isstring(L, 1))
+	if (lua_type(L, 1) == LUA_TSTRING)
 	{
 		const char *name = lua_tostring(L, 1);
 		INT32 spr = R_GetSpriteNumByName(name);
 		if (spr == NUMSPRITES)
-		{
-			char *check;
-			i = strtol(name, &check, 10);
-			if (check == name || *check != '\0')
-				return luaL_error(L, "unknown sprite name %s", name);
-		}
+			return luaL_error(L, "unknown sprite name %s", name);
 		i = spr;
 	}
 	else