Teams that will Surprise in 2015

The 2014 season is in the books.

Obviously, that means it's time to look ahead to next year, right?

Mark Schlabach recently released his Way-Too-Early Top 25. TCU is his No. 1 team entering the 2015 season, and many of the usual suspects -- Ohio State, Alabama, USC and Oregon -- rank in the top 10.

Every year, however, it seems a team comes out of nowhere to shock the college football world. In 2014, TCU, Mississippi State and Arizona were all unranked in the preseason AP Poll and won at least 10 games; Notre Dame in 2012 and Auburn in 2013 similarly surprised preseason pollsters by competing for national championships.

Which unranked team will make splash in 2015? Using many of the same components accounted for in ESPN's Preseason FPI (which will be released in the spring), below are five teams not ranked in Mark Schlabach's Top 25 that have a chance to be in the conversation by season's end.

To be included on this list, teams must satisfy certain criteria that have been found to correlate with future success:

1. A team's average overall efficiency rating the past four seasons (with 2014 weighted more heavily) must rank in the top 50.

2. A team must be returning at least 13 starters (special consideration given to teams returning their starting quarterback).

Based on these rules, here are five under-the-radar teams for the 2015 season.

1. Stanford Cardinal

2014 record: 8-5, 5-4 in Pac-12

Average Efficiency Rank: 10

Returning Starters: 13 (9 offense, 4 defense)

For the first time since the 2009 season, Stanford failed to win 10 games. Defensively, the Cardinal were the same dominant force: They ranked in the top two in points per game and yards per play allowed, despite losing All Pac-12 defenders Shayne Skov, Trent Murphy and Ed Reynolds after the previous season.

Offensively, however, the Cardinal took a step back. They were inefficient in the red zone and, uncharacteristically, struggled to run the ball.

Next season should be a different story. Stanford is returning nine offensive starters, including four offensive linemen, and a stable of young running backs. Wide receivers Devon Cajuste and Michael Rector will be back; their further development should open up the downfield passing game Stanford lacked in 2014.

The biggest question is quarterback Kevin Hogan, who has not yet made his intentions known for the 2015 season. Hogan could enter the draft or transfer, but if he returns to Stanford, he would be the most experienced quarterback in the Pac-12.

If Marcus Mariota enters the draft -- as most assume he will -- the Pac-12 North should be wide open. With David Shaw calling the shots, another down year for the Cardinal appears unlikely.