Steve Kerr refused to blame injuries as the Golden State Warriors' eight-game winning streak was ended by the Milwaukee Bucks at Oracle Arena.
NBA champions the Warriors (10-2) were beaten 134-111, losing at home for the first time this season, having seen Draymond Green sit out with a sprained toe before Stephen Curry suffered a groin strain out on the floor.
Asked for an early read on Curry's situation, coach Kerr told reporters after the game: "I don't [have an update]. I think he's going to get an MRI tomorrow [Friday]."
But the coach's main concern was with Golden State's complacency, hoping defeat to the Bucks (9-2) should provide a reminder of the difficulties of the NBA.
"I don't think it had to do with Draymond [being absent]. It had to do with our overall focus," Kerr said.
"Obviously Draymond gives us everything that he does, but when you come out with a mindless intent and you're fouling and not executing against a really good team - a team that's hungry and on the rise - you're not going to fare very well.
"It was about our approach. Sometimes you've got to get hit in the mouth in this league to remind you how hard it is to win a game. I think that's what happened.
"I think we got a little complacent. We won the last eight, were feeling pretty good about ourselves, and it's one of those nights. It happens during the NBA season.
"It's a long year and we were playing a great team who lost just two nights ago in Portland [against the Trail Blazers].
"They were hungry to get out there and I thought they played exceptionally well defensively. We didn't execute well enough to generate any momentum and get our crowd into the game."