diff --git a/src/video/x11/SDL_x11events.c b/src/video/x11/SDL_x11events.c
index c97bb6f22..4f52c6093 100755
--- a/src/video/x11/SDL_x11events.c
+++ b/src/video/x11/SDL_x11events.c
@@ -83,7 +83,7 @@ static SDL_bool X11_IsWheelEvent(Display * display,XEvent * event,int * ticks)
             if (event->xbutton.button == Button4) {
                 *ticks = 1;
             }
-            else {
+            else if (event->xbutton.button == Button5) {
                 *ticks = -1;
             }