LOS ANGELES (AFP) — The Milwaukee Bucks sacked head coach Adrian Griffin on Tuesday, in a shock dismissal that comes with the team ranked second in the Eastern Conference standings.

"This was a difficult decision to make during the season," Bucks general manager Jon Horst said 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."

Multiple US media reports said the Bucks were targeting former Philadelphia head coach Doc Rivers as Griffin's long-term replacement.

Griffin, 49, was appointed in June after the abrupt sacking of predecessor Mike Budenholzer, who was ditched after the Bucks crashed out of last season's playoffs in the first round.

At the time, Horst said Griffin had been hired for his "championship-level coaching pedigree, character, basketball acumen and ability to connect with players."

There had been few clues that Griffin's position was under threat, with the Bucks making a solid start to the season that has left them with a 30-13 record — the second best winning percentage in the league.

Griffin's last game in charge was Monday's 122-113 victory over the Detroit Pistons.

The Bucks said assistant Bucks coach Joe Prunty would be promoted to take over from Griffin in the interim until a permanent successor is appointed.

Meanwhile, Cleveland Cavaliers center Tristan Thompson has been given a 25-game suspension after testing positive for banned drugs, the NBA said.

An NBA statement said Thompson had been suspended without pay after traces of the growth hormone ibutamoren and bodybuilding supplement SARM LGD-4033 were found in his system.

Thompson will start his suspension on Wednesday when Cleveland face the Milwaukee Bucks on the road.

Thompson, 32, is in his second spell at Cleveland after rejoining the team from the Los Angeles Lakers last year.