Now he gets the Texans, who spiraled to an NFL-worst 2-14 record last season.
"He showed that he has the ability to step into difficult situations and turn them around," Houston owner Bob McNair said. "He did that at Penn State under very difficult circumstances and did an outstanding job there. We expect to see good things happen immediately."
O'Brien was 15-9 at Penn State, hit hard by NCAA sanctions levied for the Jerry Sandusky child sex abuse scandal that cost the late Paterno his job.
He was introduced on Friday, taking over for Gary Kubiak, who was fired with three games left in the Texans' dismal season. Despite Houston's collapse, many believe it is a plum position because the Texans have many talented pieces in place and could make a quick turnaround. Houston won consecutive AFC South titles before this year's disaster.
O'Brien said he spoke to many people he trusted throughout the NFL before deciding to come work in Houston.
"These people were unanimous in one thought, and that is that the Houston Texans are a top-flight organization that does things the right way," he said. "It's rare enough to be a head coach at the highest level of football. What makes this opportunity special and put it over the top for myself and my family was to work for an owner like Bob McNair."
O'Brien said he planned to meet with Houston's assistant coaches on Friday and begin making decisions on who will make up his staff.
After his first season at Penn State, O'Brien interviewed with the Jacksonville Jaguars and Cleveland Browns, among others, only to stay in State College. This time the lure of the NFL was too strong to resist.
"I love the players at Penn State and I respect their toughness and their resiliency and everything that they've demonstrated on a day-to-day basis," he said. "I do regret not being able to continue with the great kids on that team. While I tried never to mislead anyone, I understand that some people feel let down. But again, it was a decision that was a once-in-a-lifetime opportunity for me."
O'Brien was an assistant at Brown, Georgia Tech, Maryland and Duke, before joining Belichick and quarterback Tom Brady in New England. O'Brien follows Dom Capers, who led the team from its expansion season in 2002, and Kubiak as the only coaches in Texans history.
Like Kubiak, O'Brien is known as a quarterback guru, which will be important for a team searching for a solution after veteran Matt Schaub had a terrible season and was benched after six games. He was replaced by Case Keenum, but the former record-setter at the University of Houston struggled as well.
O'Brien has almost exclusively coached offense with a focus on quarterbacks, though he was a defensive end and linebacker while at Brown.
"I think that's a fantastic position to coach because of all the things that go into it," O'Brien said. "The quarterback has to be a great teammate, a hard worker, a leader, a really good practice player, a guy that's always striving for perfection ... it's a job that's never-ending. It's a job that you can always improve if you like coaching quarterbacks and it's a lot of fun to do."
Houston has the top overall draft pick and could use it on a one of a trio of talented signal-callers who could be available. Louisville's Teddy Bridgewater, 2012 Heisman Trophy winner Johnny Manziel of Texas A&M and Fresno State's Derek Carr, younger brother of Houston's first-ever draft pick, David Carr, are the top-rated quarterbacks expected to be in the draft.
"If we wound up with a young quarterback, we'd probably bring in a veteran so we don't have to depend on that rookie," McNair said. "That's tough putting a rookie in there and expecting them to be able play right off the bat. There've been a couple of them that have done it but a number of them didn't do so well. I think having that veteran presence is important."
Houston has had the first pick in the draft two other times, choosing Carr in 2002 and defensive end Mario Williams in 2006.
"The defensive player worked out better than the offensive player," McNair said with a laugh. "But that won't lock us into anything. There's always a possibility. (General manager) Rick (Smith) and the coaches will trade around. Maybe we'll trade down and still get a quarterback that can do the job and get an outstanding defensive player."
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