TAMPA, Fla. — Monte Kiffin is giving up the NFL to join his son on the sidelines in the Southeastern Conference.

Tampa Bay's longtime defensive coordinator ended weeks of speculation, confirming he will leave the Buccaneers at the end of this season for a position on the staff of Lane Kiffin, the new coach at Tennessee.

"I think we all respect his situation. We had a pretty good indication that he was going to join his son," Bucs coach Jon Gruden said Monday. "It's a great reunion, I think, for the Kiffin family. I'm happy for him."

Kiffin was unavailable for comment, however he told reporters after Sunday's 13-10 overtime loss in Atlanta that he made the decision the previous weekend and informed Gruden, general manager Bruce Allen and the players last Wednesday.

"It was a very, very hard decision. ... When you've been in a place since 1996, you don't just jump ship," Kiffin said.

"I've had other opportunities. There was one that came up last year that was a great opportunity, and people don't even know for sure about the whole thing. But I stayed here, decided to sign back up for two years. But the club was very good about giving me the option to go with my son."

Kiffin is in his 13th season of running the Bucs defense, and the unit has ranked among the best in the NFL for most of that tenure.

Even before Tennessee officially hired Lane Kiffin to replace Phillip Fulmer, there was speculation that the elder Kiffin might be interested in joining his son, who was fired earlier this season by the Oakland Raiders.

Gruden said Kiffin's impending departure won't be a distraction for the injury-depleted Bucs, who have lost two straight games but remain in contention for a playoff berth at 9-5. He also declined to speculate about a possible successor for the 68-year-old assistant.

"We're going to finish this season. We have a lot of guys that are on the last year of their contract — players, coaches, that's league-wide," Gruden said.

"I don't want to speculate. I want to finish the season. We've done so many good things. ... We're fighting through some very tough injuries and we've got to make some tough decisions on where we go next."