Four linebackers were selected in the first round of the 2012 NFL Draft on Thursday. More surprising, however, was who was left on the board. Alabama's Courtney Upshaw, rated by Mocking The Draft as the best player at any position still available and the best at his position, was passed over for the likes of West Virginia's Bruce Irvin and Boise State's Shea McClellin. Don't expect Upshaw to last long when Rounds 2 and 3 get under way Friday.

Nebraska's Lavonte David was also left on the board despite a first-round grade from MTD. He was rated as the No. 29 overall player in this year's draft, and the second-best outside linebacker available behind only Upshaw.

Other linebackers with a reasonable chance of getting drafted Friday include North Carolina's Zach Brown (No. 47 overall), Utah State's Bobby Wagner (No. 59 overall) and Nevada's James-Michael Johnson (No. 65 overall).

Check out the complete list of best players available at Mocking The Draft.

For more Draft coverage, check out our NFL Draft grades, Round 2 mock draft and the complete first-round NFL Draft results.