Wheeler matched his season-high for walks - he's now walked five batters in three of his 15 starts this season.
"It's just a bad job tonight overall for me. Not getting ahead of guys, just falling behind," Wheeler explained. "They did a good job of moving runners and stuff."
Wheeler didn't want to use fatigue as an excuse for his performance - he has said on several occasions recently he is suffering from late-season fatigue.
"Like I've said before, once you go out there, you aren't really tired," Wheeler said. "That's just in between starts you're lagging and stuff. It really didn't have anything to do with tonight."
Wheeler lost for the first time away from Citi Field with his performance against Cleveland - he is now 5-1 with a 2.32 ERA in nine starts on the road.
"That's very uncharacteristic of the way he's been pitching. The one thing that we've talked about in the last month is that he's 'pouring' the strike zone. Tonight he was missing."
Still, Collins was pleased with Wheeler's ability to limit the damage.
“That’s a sign that he has matured over his 15 major league starts,” Collins continued. “He is not trying to strike guys out, which he might have tried when he first got here. He’s trying to get outs. He’s really gotten better.”