The Toronto Raptors sacked head coach Dwane Casey following their Eastern Conference semi-final sweep at the hands of the Cleveland Cavaliers.

Weeks removed from wrapping up the most successful regular season in Raptors history after securing the top seed in the east, Toronto relieved Casey of his duties on Friday.

The Raptors won a franchise-record 59 games and entered the playoffs as the number one team in the Eastern Conference, but a second-round sweep to the Cavaliers showed how far Toronto have to go.

"After careful consideration, I have decided this is a very difficult but necessary step the franchise must take. As a team, we are constantly trying to grow and improve in order to get to the next level," Raptors president Masai Ujiri said.

"We celebrate everything Dwane has done for the organisation, we thank him, and we wish him nothing but the best in future. He was instrumental in creating the identity and culture of who we are as a team, and we are so proud of that."

The announcement comes two days after Casey was named Coach of the Year by his peers.

Interestingly, the last time a reigning Coach of the Year was fired was Denver Nuggets boss George Karl following the 2012-13 season and shortly after Ujiri left the Nuggets for the Raptors. 

Casey went 320-230 (.573) in seven seasons in Toronto, reaching the playoffs on five consecutive occasions and winning at least 50 games three times.