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For all the years Bill Belichick and Romeo Crennel have coached in the NFL, the Week 11 matchup between the New England Patriots and the Houston Texans will be just the second time the coaches have squared off against each other. The last time Belichick and Crennel matched up as head coaching opponents was in Week 5 of the 2007 season, when Crennel was in his third season coaching the Cleveland Browns and Belichick was in his eighth year with New England. 

Belichick and Crennel have been on the same coaching staff for a long time, the most notable stint from 2001 to 2004, when Crennel was the defensive coordinator for Belichick's first three Super Bowl titles with the Patriots. Belichick owes Crennel plenty for his coaching success in the NFL, deeming his former assistant the best coach he's ever worked with. 

"He's a great addition to any staff," Belichick said Wednesday. "I had been very, very fortunate to work with him throughout my career, starting with the Giants when he came in '81 and we spent a lot of time together. I've learned so much from him. He's an excellent teacher, a great communicator, motivator, fundamental coach with a very good grasp of the big picture, as well as the finer details of pretty much every position and every little scheme. 

"So, I've been very fortunate to work with a lot of great coaches in my career, but he would be at the very top of that list. I think the world of him and appreciate his friendship and have a tremendous amount of respect for what he's accomplished in his career and great appreciation for all that he's done to not only help me as a head coach, but when we were both assistants and we worked alongside each other, he was a great teammate and person that I learned probably a lot more from than I would have taught him. He's a great man, a great coach."

Crennel came to the Giants in 1981 as a special teams coach and a defensive assistant, working with Belichick on Bill Parcells' staff (Belichick joined the Giants with Parcells in 1979). He served as a special teams coach until 1989 before being promoted to defensive line coach. When Parcells was hired by the Patriots in 1993, Crennel joined him on his staff as the defensive line coach as Belichick reunited with him in 1996 after his firing from the Cleveland Browns. Crennel and Belichick served under Parcells on the New York Jets coaching staff for three years, as Crennel was a defensive line coach under Belichick -- who was the defensive coordinator. 

Belichick hired Crennel in 2001 to be his defensive coordinator and New England finished with a top 10 scoring defense in three of his four seasons -- including a top-two ranking in 2003 and 2004. Belichick and Crennel haven't coached together since the Patriots defeated the Philadelphia Eagles in Super Bowl XXXIX as Crennel was hired by the Cleveland Browns to become their next head coach. 

Crennel has served as the Texans defensive coordinator since the 2014 season and is currently the team's interim head coach after the team fired Bill O'Brien last month. Sunday's matchup between the two coaches is the oldest head coaching matchup in NFL history. 

"It was great," Crennel said on his experience working with Belichick. "It was a great opportunity for me because I was a young college coach when I got in and Belichick was already there and he had a couple of years under his belt at a young age. But, he's very analytical. He studies offense, defense, special teams. He's coached most positions on the football field. I think all of those experiences helped make him the successful head coach he is."