Steve Kerr warned the United States must not "get lulled to sleep" by the fact they have already beaten Serbia twice recently. (Medal Table | Schedule & Results | Full Coverage)
The USA cruised past Brazil to reach the semi-finals of the Olympics, and Nikola Jokic's Serbia are next up.
Serbia have already faced the USA in the group stage, with the four-time reigning Olympic champions winning 110-84.
The USA also beat Serbia by 26 points in a warm-up match prior to the Games, but Kerr is taking nothing for granted ahead of Thursday's clash.
He said: "We can't get lulled to sleep because we beat them twice.
"We have to be prepared for their best effort. We've got to think about what they are going to do differently.
"Jokic, I guess he could play 40 minutes. What else do they have up their sleeve?"
It was a sentiment echoed by LeBron James.
"Every game is its own test. No matter what happened in the first two, it's about what goes down Thursday night," he said.
"So we need to lock in our film session, lock in during the day on Thursday, and then come out and be ready to go."
Jokic inspired Serbia to an Olympic-record comeback against Australia in the quarters.
How Serbia plan to manage Jokic's minutes is an intriguing question, but Joel Embiid is setting himself up to face the reigning NBA MVP for over 40 minutes.
"I guess we'll be ready for that," said Embiid.
"If that's what they think they have to do to try to beat us, then they won't hesitate to do that."
