TAMPA, Fla. -- Tampa Bay Buccaneers defensive coordinator Mike Smith interviewed with San Diego on Thursday for their head coaching position. In fact, the Chargers announced that he was their first interview. He's also interviewing with Jacksonville. Bucs head coach Dirk Koetter indicated this week that the team is preparing for the possibility of Smith's departure and is looking at potential options for a replacement, should he be hired away.

"Obviously when we brought Mike here, we knew that this day might come and this day would come," said Koetter. "And if it’s the right fit and he’s the right guy and that’s what he wants and that’s what they want, there’s nothing I can do about it, that’s how this league works. What I can tell you is, I’ve got a lot of confidence in the staff that I put together last year, and I’ve got a lot of confidence in the staff I’ll put together moving forward."

Smith did a commendable job with the defense in the second half of the season, where they went from averaging 399 yards and 29 points allowed per game in the first eight games, 28th and 29th in the league respectively, to giving up 337 yards (13th in the league) and 17 points per game (fourth). In the final eight games, they posted a 32 percent third-down conversion rate, third-best in the league, and 18 takeaways, the most in the league.

With that transformation in mind, the Bucs might want to look inside their own building first for potential replacements. Although no two coaches are exactly alike, it would allow for continuity in the Bucs' scheme -- a flexible 4-3 defense running Cover 2, Cover 3, Cover 4 and Cover 0 that only blitzed about 15 percent of their snaps, that did a particularly good job of disguising coverages on the back-end and showed good tackling on the perimeter. There's just not a whole lot of defensive coordinator experience in that room after Smith.

Linebackers coach Mark Duffner has some coordinator experience from when he was with Cincinnati, serving as defensive coordinator, along with linebackers coach from 2001-2002, and he spent two of his eight season with the Jaguars working in Mike Smith's defense. The question is, and it's something those close to him are wondering as well -- would he want to be a coordinator or does he want to continue as a position coach? In his four coaching stints after Cincinnati, he was a linebackers coach.

Defensive line coach Jay Hayes presents another intriguing option. Prior to coming to Tampa, he spent 13 years in Cincinnati as Marvin Lewis' defensive line coach. In the final eight weeks of the season, his group registered 21 sacks, tied for fifth-best in the league during that span. For the entire season, they recorded 38 sacks, ninth in the league. Prior to his time in Cincinnati, he was the special teams coach in Pittsburgh (1999-2001) and Minnesota (2002).

If the team opted to go outside the building, which would give them more coordinator experience, former Jaguars head coach Gus Bradley would be a terrific option. He cut his teeth in Tampa as the linebackers coach under Monte Kiffin, with his greatest success coming in Seattle as Pete Carroll's defensive coordinator.

If Bradley came aboard, it would probably require some scheme and terminology adjustments. The Jaguars use positions such as the Otto, Elephant and Leo. Bradley did say this season in Jacksonville that he was open to adjusting his scheme to best-fit the needs of his players. That's a plus. If that's the case, the Bucs might end up with a defense that has a similar look to what Dallas is running under Rod Marinelli. Would Bradley keep the remaining staff intact? That's another factor the team would have to consider.

One thing that's very important to note regarding coordinator candidates: teams can block those interviews if assistants are under contract. A common misconception is that teams cannot block promotions of position coaches to coordinators, and that is simply not true -- it only applies to coaches who are being interviewed for head coaching positions.