Seven weeks after being convicted of sexual assault, Bill Cosby, who is awaiting sentencing, fired his legal team led by Tom Mesereau, a high-profile lawyer who successfully defended Michael Jackson but could not help Mr. Cosby.

Mr. Cosby’s publicist, Andrew Wyatt, confirmed the change on Thursday in an email.

“The entire defense team has been replaced,” he wrote without elaborating.

Mr. Wyatt said Mr. Cosby’s new lawyer is Joseph P. Green, who is based in West Chester, Pa., and whose practice includes criminal defense and personal injury cases. Mr. Green did not return a phone call seeking comment.

Mr. Mesereau declined to explain why he is no longer representing Mr. Cosby, saying only: “I wish Mr. Cosby, his family and his new legal team all the best.”

Mr. Cosby, 80, is facing up to 30 years in prison after being convicted in April on three counts of aggravated indecent assault. The jury was unable to reach a verdict in his first trial, in 2017. But at the retrial in April the jurors found that Mr. Cosby had drugged and then molested Andrea Constand, a former Temple University basketball official, at his home outside Philadelphia in 2004. He is to be sentenced in September.

After the first trial, Mr. Cosby also replaced a legal team, that one led by Brian J. McMonagle, a Philadelphia defense lawyer. Mr. McMonagle declined to comment on the latest change.

William J. Brennan, a defense attorney from the Philadelphia area, said Thursday that Mr. Cosby should have stuck with Mr. McMonagle, who was able to sow enough doubt in jurors’ minds that they were unable to agree on a verdict.

“If he had a brain in his head, he would go back to McMonagle,” Mr. Brennan said.

Philadelphia-area defense attorneys said it’s not unusual for those convicted to hire new lawyers, especially if they are filing an appeal. Mr. Mesereau announced in April that an appeal was planned, though such legal efforts typically do not begin until after sentencing.

Alan Tauber, a Philadelphia-area defense attorney, said it’s not clear why Mr. Cosby replaced Mr. Mesereau’s team, which Mr. Tauber said had taken a notably aggressive approach at the retrial, arguing that Ms. Constand was lying about the assault to set up Mr. Cosby because she wanted a big payout.

Kate Delano, a spokeswoman for Kevin Steele, the Montgomery County district attorney who prosecuted Mr. Cosby, said Mr. Steele was aware of the defense change but would have no comment.