Penn State coach Bill O'Brien is the leading candidate to be the Houston Texans next coach, a source close to the search tells CultureMap.

The Texans began putting early back channel feelers out to various coaches to gauge their potential interest even before Gary Kubiak was officially fired on Dec. 6 and have a very good idea at this point who is legitimately in play as a candidate and who is not, the same source says. From that sorting, O'Brien's emerged as the Texans No. 1 target.

O'Brien separated himself with the poise he's shown under extreme circumstances at Penn State University, his NFL experience under New England Patriots head coach Bill Belichick and his track record of getting the best out of quarterbacks. He will take a big edge into an interview with the Texans.

More importantly for a Texans franchise still reeling from the Kubiak-Schaub marriage, O'Brien's built something of a reputation as a QB whisperer.

Any NFL team that hires O'Brien would have to pay a $6.7 million buyout to Penn State — in addition to a multi-million dollar deal for O'Brien — but that's not a major issue for Texans owner Bob McNair, according to CultureMap's source.

Instead the Texans owner is focused on making a hire who can make an immediate impact and impart a culture change. It's about ensuring he and general manager Rick Smith make the right hire rather than just an economical hire.

Former Chicago Bears coach Lovie Smith — whose name has been mentioned as a Texans candidate — being untied to another team or university hasn't raised his candidacy to Bill O'Brien's level.

O'Brien wouldn't come without some questions. The 44-year-old has only been a head coach at any level for two seasons. And other Belichick coaching disciples have hardly consistently torn up the NFL. But O'Brien's 8-4 and 7-5 seasons at Penn State look almost Belichick-like when you consider he took over a program reeling from horrifically, unprecedented Jerry Sandusky child abuse scandal.

Despite operating under severe scholarship restrictions and a bowl ban, O'Brien's teams tend to get better as the season goes on. Penn State lost to lowly Ohio University in O'Brien's first game in Happy Valley last year and he still ended up winning the Bear Bryant Coach of the Year Award (which happens to be given out in Houston).

Perhaps even more importantly for a Texans franchise still reeling from the Gary Kubiak-Matt Schaub marriage, O'Brien's built something of a reputation as a quarterback whisperer. Whether it's with Tom Brady or an 18-year-old true freshman named Christian Hackenberg.

O'Brien was the offensive coordinator in New England in 2011 when Brady passed for the second most yards in NFL history (5,235) and made it back to the Super Bowl. And Hackenberg just won Big Ten Freshman of the Year honors under O'Brien at Penn State.

Other NFL teams will reach out to O'Brien (the Minnesota Vikings have reportedly also already contacted him) and Penn State will make a push to keep its program steadier. And the Texans will interview other candidates — this isn't a franchise that completely rushes into things or ignores sound NFL regulations such as The Rooney Rule.

Still, the Texans wish list is clear. And one name's at the top of it right now.