The Milwaukee Bucks fired Adrian Griffin as coach on Tuesday after just 43 games despite having one of the league's top records midway through his first season.
The Bucks are planning to quickly pursue a small pool of accomplished and available veteran head coaches -- with Doc Rivers as a top target, sources told ESPN's Adrian Wojnarowski. The Bucks have reached out to Rivers and are in conversations about the franchise's coaching job, sources said.
"This was a difficult decision to make during the season," said Bucks General Manager Jon Horst in a statement. "We are working immediately toward hiring our next head coach. We thank Coach Griffin for his hard work and contributions to the team."
Veteran assistant Joe Prunty will take over as interim coach. Horst will speak at a news conference Wednesday, before the Bucks' next home game with the Cleveland Cavaliers.
Milwaukee hired Griffin over the summer to replace longtime coach Mike Budenholzer, who was fired after Milwaukee's first-round exit last postseason. Months after the hire, the Bucks swung a blockbuster trade to acquire Damian Lillard -- putting pressure on the franchise to win big this season.
The Bucks are 30-13 and entered Tuesday night's games No. 2 in the Eastern Conference; that's the best winning percentage for a team that fired its head coach during a season since David Blatt with the Cavaliers in 2015-16.
But despite the impressive record, the Bucks have struggled at times, particularly on defense. They've slipped from fourth on defense last season to 22nd this year and just gave up 135 and 113 points in back-to-back games against the Detroit Pistons.
Griffin, 49, had spent 16 seasons as an NBA assistant, including the past five with the Toronto Raptors. That followed a nine-year NBA playing career.
The Associated Press contributed to this report.