diff --git a/ui/overviewcanvas.py b/ui/overviewcanvas.py
index 0bf3d455..5b12e9cd 100644
--- a/ui/overviewcanvas.py
+++ b/ui/overviewcanvas.py
@@ -320,7 +320,7 @@ class OverviewCanvas:
         for cp in self.game.theater.controlpoints:
             coords = self._transform_point(cp.position)
             radius = 12 * math.pow(cp.importance, 1)
-            radius_m = radius * cp.base.strength - 2
+            radius_m = max(radius * cp.base.strength - 2, 0)
 
             if cp.captured:
                 color = self._player_color()