ESPN draft expert Mel Kiper has two Big 12 players -- Oklahoma’s Lane Johnson and Texas’ Kenny Vaccaro -- potentially going in the first round of this year’s NFL draft.

Fellow expert Todd McShay has the same two as Kiper and also is optimistic about the chances of West Virginia’s Geno Smith and Tavon Austin.

So let’s split the difference and label the potential Big 12 first-round picks as an optimistic three, with Johnson being the only absolute first-round lock.

Those three would represent the fewest Big 12 players taken in the first round of the NFL draft since 2008. Even if four went, the Big 12 still would have the fewest since 2008.

That year, only Kansas -- yep, the Jayhawks -- managed a first-rounder, Aqib Talib to Tampa Bay with the 20th pick. In the four drafts that followed, the Big 12 has always put at least five players into the first round, including the first four overall picks in 2010.

How well this year’s group of first-round picks will fare might not be known for years. What is known, though, is how well Big 12 players have done when they are selected in the first round. With that in mind, here is a ranking -- from worst to best -- of the Big 12’s best first-round draft classes over the past 10 years.

2008: It’s all about quantity, and a little bit of quality. In 2008, the Big 12 only produced one first-round pick, Talib. He has not produced dramatic returns in the NFL. In the past two years, he has only started nine games. He was somewhat productive for Tampa Bay in the previous three seasons, starting 41 games and playing in 53. But, again, he was the only Big 12 player taken in the first round in 2008.

2006: Vince Young is working out at Texas’ pro day at the end of March. Enough said. Davin Joseph and Michael Huff have been solid producers. But when the No. 3 overall pick is out of the league and having to work out at his alma mater's pro day, it means it was a bad year for the Big 12 in the first round of the NFL draft.

2004: Tommie Harris and Marcus Tubbs, the two defensive tackles taken in the first round, were productive for a few years, with Harris selected to Pro Bowls in 2005, '06 and ’07 before he was beset by injuries. Tubbs lasted four seasons in the NFL. Roy Williams had 5,715 receiving yards but never lived up to the hype he generated coming out of Texas. Rashaun Woods played only two years and had seven career catches.

2005: The lack of numbers might be what hurts this group the most. Cedric Benson, Jammal Brown, Derrick Johnson, Mark Clayton and Fabian Washington all proved they could play at the NFL level. Benson has had three 1,000-yard-plus seasons. Johnson is one of the top linebackers in the game. Brown remains a solid option on the offensive line. Clayton played seven NFL seasons; Washington played six. But there were only five guys selected and that isn't enough to push 2005 to the top of the list.

2009: Every Big 12 player selected in the first round in 2009 has produced and appears to be poised to continue to do so. Only Jason Smith didn’t have a start last year. But the offensive lineman still played in all 16 games for the New York Jets. Michael Crabtree, Brian Orakpo, Josh Freeman, Jeremy Maclin, Brandon Pettigrew and Ziggy Hood are all starters for their respective teams.

2007: It wasn’t the biggest group, but it did include Adrian Peterson, so there could be some quibbling that maybe 2007 should be higher in the rankings. Throw in Aaron Ross and Michael Griffin and the debate could get even more heated. Adam Carriker was also taken this year. He started his career strong but suffered an injury and only played in two games last season.

2003: Kevin Williams has been the standout of this group. The defensive tackle has started every game but four in his 10-year career. Terence Newman has been effective as a defensive back, first in Dallas and last season in Cincinnati. Tyler Brayton played at least 15 games on the defensive line in a nine-year career. Ty Warren played eight solid seasons for New England but tailed off last season with Denver. Andre Woolfolk lasted four seasons, mostly as a reserve.

2011: Von Miller, who was the highest pick among Big 12 players this year, has proved to be the top player so far. Aldon Smith is not far behind. Add in Prince Amukamara, Phillip Taylor, who when healthy is a starter at defensive tackle, a somewhat productive Blaine Gabbert and Nate Solder as well as reliable backups Danny Watkins and Jimmy Smith and this proved to be a successful year for Big 12 first-round selections.

2012: Three quarterbacks, and all were not only starters as rookies but also made huge differences for their respective squads. Clearly, Robert Griffin III made the most dramatic impact, but Ryan Tannehill, with the Dolphins, and Brandon Weeden, with Cleveland, were both solid. Kendall Wright and Justin Blackmon each had 64 catches, for Tennessee and Jacksonville, respectively. Blackmon was targeted more (133 to 104) and had 200 more receiving yards.

2010: This list maybe doesn’t have the star power and is not littered with offensive playmakers, but six of the nine players picked were selected for the 2013 NFL Pro Bowl: Gerald McCoy, Trent Williams, Ndamukong Suh, Earl Thomas, Russell Okung and Jermaine Gresham. And the other three players -- Dez Bryant, Sam Bradford and Sean Weatherspoon -- were vital pieces for their respective teams.