diff --git a/src/battle_script_commands.c b/src/battle_script_commands.c
index 0ee6e1b698..95ad77ff53 100644
--- a/src/battle_script_commands.c
+++ b/src/battle_script_commands.c
@@ -2828,7 +2828,11 @@ void SetMoveEffect(bool32 primary, u32 certain)
                 }
                 break;
             case MOVE_EFFECT_KNOCK_OFF:
-                if (GetBattlerAbility(gEffectBattler) == ABILITY_STICKY_HOLD)
+                if (!CanBattlerGetOrLoseItem(gEffectBattler, gBattleMons[gEffectBattler].item))
+                {
+                    gBattlescriptCurrInstr++;
+                }
+                else if (GetBattlerAbility(gEffectBattler) == ABILITY_STICKY_HOLD)
                 {
                     if (gBattleMons[gEffectBattler].item == 0)
                     {
@@ -2840,9 +2844,8 @@ void SetMoveEffect(bool32 primary, u32 certain)
                         gBattlescriptCurrInstr = BattleScript_StickyHoldActivates;
                         RecordAbilityBattle(gEffectBattler, ABILITY_STICKY_HOLD);
                     }
-                    break;
                 }
-                if (gBattleMons[gEffectBattler].item)
+                else if (gBattleMons[gEffectBattler].item)
                 {
                     side = GetBattlerSide(gEffectBattler);
 
diff --git a/src/battle_util.c b/src/battle_util.c
index 007a863a2e..1b8ad6fcf1 100644
--- a/src/battle_util.c
+++ b/src/battle_util.c
@@ -6383,7 +6383,9 @@ bool32 CanBattlerGetOrLoseItem(u8 battlerId, u16 itemId)
         return FALSE;
     else if (species == SPECIES_GROUDON && itemId == ITEM_RED_ORB)
         return FALSE;
-    else if (ItemId_GetHoldEffect(itemId) == HOLD_EFFECT_MEGA_STONE && GetMegaEvolutionSpecies(species, itemId) != SPECIES_NONE)
+    // Mega stone cannot be lost if pokemon can mega evolve with it or is already mega evolved.
+    else if (ItemId_GetHoldEffect(itemId) == HOLD_EFFECT_MEGA_STONE
+             && ((GetMegaEvolutionSpecies(species, itemId) != SPECIES_NONE) || gBattleStruct->mega.evolvedPartyIds[GetBattlerSide(battlerId)] & gBitTable[gBattlerPartyIndexes[battlerId]]))
         return FALSE;
     else if (species == SPECIES_GIRATINA && itemId == ITEM_GRISEOUS_ORB)
         return FALSE;