NASHVILLE, Tenn. -- Titans coach Mike Munchak has fired offensive coordinator Mike Heimerdinger along with two other assistants as he starts to remake his coaching staff a day after taking over the top job.

Heimerdinger, who is continuing cancer treatment after diagnosed in November, confirmed to The Associated Press on Tuesday that he had been fired. The Titans released a statement a couple hours later that Munchak also told defensive assistant Rayna Stewart and offensive assistant Richie Wessman that they will not be retained.

"It's never easy to be fired," Heimerdinger said. "He has to do what's good for the Titans, and Munch will do what's best for the Titans. I appreciate my time here, but it's never easy to be fired."

The Titans gave Munchak the freedom to keep or hire anyone he wants and he promised changes when he was introduced on Monday. He let go the coordinator who was the second coach interviewed to replace Jeff Fisher. Munchak said it wasn't an easy move involving a man he respects as an innovative offensive mind and for how he has fought cancer.

"We have worked well through the years, but I believe we need to go in a different direction at offensive coordinator," Munchak said. "This wasn't about his health -- he is feeling good -- it is a change of direction for us. This is not something that I take lightly and I wish him and his family the best."

The Titans also defended themselves for firing a man with cancer. Senior executive vice president Steve Underwood said in the team's statement that the Titans immediately offered to extend Heimerdinger's contract when he diagnosed. Heimerdinger was under contract for 2011.

"We will honor Mike's existing agreement with our club and continue to wish him a complete recovery," Underwood.

This now gives Munchak eight openings to fill on his coaching staff. Fisher had fired defensive coordinator Chuck Cecil last month, while the defensive line coach, running backs coach and wide receivers assistant all left for other jobs. Former teammate Bruce Matthews, now an assistant in Houston, is expected to be Munchak's top target to fill his old job with the offensive line.

The news brought almost instant reaction Tuesday.

Titans safety Michael Griffin wrote on Twitter that, "People thought it was a joke when I said no one is safe."

This was Heimerdinger's second stint as offensive coordinator with Tennessee. He helped Steve McNair earn co-MVP of the NFL honors in 2003 and was part of three playoff teams in his first five seasons before leaving for the same job with the Jets in 2005. Fisher brought him back in 2008 after two seasons in Denver.