after John Thornton suffered a wrist injury. He finished the Bengals' 13–7 win against the Baltimore Ravens with two combined tackles. In Week 16, Peko recorded six combined tackles and made a season-high two sacks on Broncos' quarterback Jay Cutler in the Bengals' 24–23 loss at the Denver Broncos. He finished his rookie season in 2006 with 43 combined tackles (21 solo), 2.5 sacks, and two forced fumbles in 16 games and one start. 2007 Throughout training camp in 2007, Peko competed to be a starting defensive tackle against Michael Myers, John Thornton, Kenderick Allen, and Matt Toeaina. Head coach Marvin Lewis named Peko a starting defensive tackle to begin the 2007 NFL season. He started alongside John Thornton and defensive ends Justin Smith and Robert Geathers. In Week 8, Peko recorded three combined tackles and made his first career solo sack on Steelers' quarterback Ben Roethlisberger during the third quarter of the Bengals' 24-13 loss to the Pittsburgh Steelers. On December 15, 2007, he collected a season-high nine combined tackles and was credited with half a sack in the Bengals' 20-13 loss at the San Francisco 49ers in Week 15. He started in all 16 games in 2007 and recorded 52 combined tackles (36 solo), 1.5 sacks, a pass deflection, and a fumble recovery. 2008 On January 2, 2008, the Cincinnati Bengals fired defensive coordinator Chuck Bresnahan after the defense ranked 27th in the league for total defense in 2007. On January 15, 2008, the Cincinnati Bengals named former Atlanta Falcons' defensive coordinator Mike Zimmer as their new defensive coordinator. Zimmer retained Peko and John Thornton as the starting defensive tackles in 2008. On July 13, 2008, the Cincinnati Bengals signed Peko to a five-year, $27.70 million contract that includes $8.50 million guaranteed. On October 12, 2008, Peko collected a season-high eight combined tackles in the Bengals' 26-14 loss at the New York Jets in Week 6. Peko started in all 16 games in 2008 and recorded a career-high 67 combined tackles (29 solo), two passes defended, and was credited with half a sack. 2009 Peko returned as a starting defensive tackle in 2009 and started alongside Tank Johnson and defensive ends Robert Geathers and Antwan Odom. In Week 4, he collected a season-high five combined tackles during a 23–20 win at the Cleveland Browns. On November 29, 2009, Peko made one tackle before exiting in the third quarter