2013 NFL Combine: Onterio McCalebb, Knile Davis highlight RB workouts

McCalebb and Davis were the only two running backs to break 4.4 seconds in the 40-yard dash.

Welcome to the NFL Scouting Combine, where Auburn running back Onterio McCalebb just broke Chris Johnson's record in the 40-yard dash with a 4.21 — and then didn't, as the official time came out as a 4.34.

McCalebb initially timed out at 4.27 and 4.21 in his two attempts at the 40-yard dash, but the official clock had him at 4.34, tied with West Virginia wide receiver Tavon Austin and Texas A&M wide receiver Ryan Swope for the second-fastest time of the year. Texas wideout Marquise Goodwin was tops with an official 4.27.

McCalebb's lack of size and physicality, however, makes him a fringe prospect at best. Regardless of if or when he gets drafted, McCalebb's times were impressive, particularly the near record-breaker.

Chris Johnson certainly wasn't all that impressed with McCalebb's time.

Listen 4.21 thats childish
— Chris Johnson (@ChrisJohnson28) February 24, 2013

But Johnson was more worried than he let on. After McCalebb's official time came out shy of the record, Johnson admitted he was nervous.

Can't lie that one scared me
— Chris Johnson (@ChrisJohnson28) February 24, 2013

McCalebb wasn't the only impressive running back during Sunday's workouts. Arkansas' Knile Davis, who has dealt with some serious injuries in his college career, ran a 4.37 in the 40-yard dash after weighing in at 220 pounds and putting up 31 reps on the bench press. Perhaps he has finally put the injuries behind him.

Christine Michael also stood out, clocking in at 4.54 in the 40-yard dash, hitting 43 inches on his vertical jump and putting up 27 reps on the bench press all at 220 pounds. He's certainly come into this process with a chip on his shoulder after a rough senior season.

Clemson's Andre Ellington, meanwhile, pulled up short on his 40-yard dash with an injury but still managed a time of 4.61 seconds.

McCalebb and Davis were the only two running backs to break 4.4 seconds in the 40-yard dash and only two others were under 4.5 seconds.

Check out the full results here.