diff --git a/init.lua b/init.lua
index ad5ca19..5cf7cb8 100644
--- a/init.lua
+++ b/init.lua
@@ -27,6 +27,7 @@ local monoids = minetest.get_modpath("player_monoids")
 local pova_mod = minetest.get_modpath("pova")
 local armor_mod = minetest.get_modpath("3d_armor")
 local timer = 0
+local math_min = math.min
 
 -- main function run for each player
 
@@ -282,7 +283,7 @@ local function punchy(
 	end
 	-- END tool damage
 
-	local kb = math.min(32, damage * 2)
+	local kb = math_min(32, damage * 2)
 
 --print ("--- knockback", player:get_player_name(), damage, kb)