The Toronto Raptors fired coach Dwane Casey on Friday, the team announced.

Casey, the most successful coach in franchise history, lost his job after consecutive second-round playoff sweeps to the Cleveland Cavaliers and being named the coach of the year in a vote of the NBA's 30 coaches.

"After careful consideration, I have decided this is a very difficult but necessary step the franchise must take," Raptors president Masai Ujiri said in a statement. "As a team, we are constantly trying to grow and improve in order to get to the next level. We celebrate everything Dwane has done for the organization, we thank him, and we wish him nothing but the best in the future. He was instrumental in creating the identity and culture of who we are as a team, and we are so proud of that."

Casey had one year left on his contract, worth $6.5 million.

The Raptors set a franchise record with 59 regular-season victories and earned the East's No. 1 seed before advancing to the Eastern Conference semifinals with a 4-2 series victory over the Washington Wizards.

The Raptors' record improved in six of seven seasons under Casey. He could quickly become a top candidate for the coaching jobs available, including in Detroit.

"Case is one of the best coaches I've ever had," point guard Kyle Lowry told ESPN. "We didn't always see eye to eye, but he let me be me. He allowed me to go out and express myself as a player, and both DeMar [DeRozan] and I ended up becoming four-time All-Stars and leaders here. He was huge for my growth as a man and an NBA player.

"They made a decision -- and for me, as a leader in the organization -- it's my job to support the decision that Masai and [general manager] Bobby [Webster] made."

Lowry said the Raptors did a lot of things well under Casey.

"We have continued to get better," Casey said. "We just didn't play well this season at the right time. It's tough to simply say [as a team], 'Well, we're not good enough together.'"

Boston Celtics coach Brad Stevens expressed disappointment in Friday's announcement, saying Casey is "a role model for a lot of coaches when you think about how his great players got better, played great."

Said Cleveland Cavaliers coach Ty Lue of Casey: "For what he's done for that team and the culture of that team, his accolades speak for themselves. I mean, he got Coach of the Year and then you get fired the next day. So, I mean, that's crazy."

For his part, LeBron James said he isn't paying attention to social media chatter that he caused Casey's dismissal by leading the Cavaliers to a sweep of the Raptors.

"I'm the last guy to ask about what people are saying on social media. That's not a field of my life at all," James said. "It sucks that with the great season that they had, and I'm just going off my own mind right now, just looking at the level of success they've had over the last three, four years maybe. ... But I guess their front office wants playoff success. That's what it boils down to, I guess."

Former Atlanta Hawks coach Mike Budenholzer is expected to get a close inspection for the Raptors opening, league sources said. Budenholzer met with Milwaukee on Tuesday, league sources said.

Toronto will also consider assistant Nick Nurse and G League coach Jerry Stackhouse, league sources said.

ESPN's Chris Forsberg and Dave McMenamin contributed to this report.