Just days after Bill O'Brien left the Nittany Lions for the Houston Texans, Penn State is reportedly close to a replacement head coach.

Penn State athletic director David Joyner said, according to ESPN, said the school's next head football coach could be announced "in a matter of days rather than weeks." A national search is currently underway and no candidates appear to be generating any more buzz than the other.

Joyner said past ties with the school will not matter and, without mentioning who, said a "number of prominent head coaches" have reached out to him. He also declined to say if any candidates had been formally interviewed.

In the mean time, however short it may be, defensive line coach Larry Johnson will serve as the interim head coach, performing recruiting and corresponding to the current class.

Here are five potential candidates for the Penn State head football coach job.

1.     Greg Schiano was mentioned as a candidate before the Tampa Bay Buccaneers fired him and before O'Brien left Penn State. He denied connection to the Penn State job likely because of his employment status, but now, he is very much available.

2.     According to the Centre Daily Times, Tennessee Titans head coach Mike Munchak is a possible fit. He is a Penn State alum and was reportedly considered before the school hired O'Brien. As head coach of the Titans, Munchak is 22-26 in three seasons and may be in danger of losing his job.

3.     James Franklin seems ready to move on from Vanderbilt and has been rumored to be a candidate Texas is eyeing to replace Mack Brown. PennLive.com pointed out that Franklin, while an attractive candidate, reportedly highly values his defensive lines coach. At Penn State, Johnson fills that role and has for a long time and Joyner is not likely fire Johnson in favor of Franklin.

4.     Al Golden was also previously rumored to be a target of interest for Penn State and, also like Munchak, he is an alum. However, he is 49-49 - spending 2006-2010 with Temple and 2011-now at Miami - as a head coach and is 0-2 in bowl games.

5.     Larry Johnson is the last link to the Joe Paterno era, but, more than that, he is a respected figure on the team. He has also been one of the most consistently great position coaches in the game since 1996. Thanks in part to Johnson, Penn State has produced several NFL-caliber defensive linemen and linebackers.