In the wake of a disappointing five-loss regular season, changes are in fact coming to USC.

Troubled by lingering defensive issues, the Trojans’ assistant head coach Monte Kiffin intends to resign following the team’s bowl game next month, the school announced Thursday night.

Stepping down · Assistant head coach Monte Kiffin will leave USC after three years coaching under his son, Lane. He is expected to return to the NFL, where he previously coached for 26 years. – Carlo Acenas | Daily Trojan

Kiffin will “pursue opportunities” in the NFL according to the statement. He previously spent 26 years as an assistant, including 13 seasons with the Tampa Bay Buccaneers as defensive coordinator.

“I wanted to make this announcement now so that our players who are preparing for the bowl game and our recruits who will be visiting campus are aware,” Kiffin said. “I really enjoyed my time at USC and the opportunity I had to work with our players and coaches. The chance to work for my son, Lane, was unique and memorable, but we always treated each other professionally on a coach-to-coach basis.”

The architect of the famed “Tampa 2” defense, which led the Bucs to a Super Bowl championship in 2003, Kiffin has served as the de facto defensive coordinator for the Trojans since arriving as an assistant in January 2010 along with Lane, the team’s third-year head coach.

“I respect my father’s decision and his desire to return to the NFL,” USC coach Lane Kiffin said. “We are very appreciative of the hard work and effort that he put in at USC these past three years. He has a tremendous passion for coaching young men and he is a phenomenal recruiter.”

But the Trojans’ defensive unit never quite clicked under the elder Kiffin’s tutelage. In 2010, it allowed, on average, 26.7 points and 400 yards per game, the worst statistical performance in school history.

Though making strides a season later, USC regressed in 2012, ranking 63rd nationally in total defense after surrendering 396.1 yards per game. It gave up an average of 500 yards in each of its five losses — including a record number for points (62), touchdowns (nine) and yards (730) against Oregon on Nov. 3 at the Coliseum. The week prior, versus Arizona, the Trojans gave up 39 points to the Wildcats on 588 yards.

The team’s five losses overall also marked the most for a preseason Associated Press No. 1 team since 1964, when Ole Miss finished 5-5-1.

“Although things didn’t always go as well as we would have liked this year from a defensive and win-loss standpoint, I will leave USC with the utmost respect for the University, the Trojan Family and, most importantly, the players I had the good fortune to coach,” Monte Kiffin said. “I see great things ahead for the USC football program.”

According to the statement, USC plans to find a replacement for the 72-year-old coach.

Added Lane Kiffin: “The timing of this allows us to move forward now in the hiring of a new coach.”

To what capacity a replacement would serve remains unclear. Ed Orgeron is listed as the team’s defensive coordinator, although Monte Kiffin had functioned in that capacity, running defensive meetings and calling the defensive plays for the last three seasons.