Florida running back Chris Rainey, who confidently said he expected to run a 4.1-second 40-yard dash and "definitely" would break the Combine record, posted an unofficial 4.37 on his first attempt Sunday. That equaled Oregon's LaMichael James for the fastest times among the running backs so far. (40-yard dash results)
Miami's Lamar Miller is being credited with a 4.38 and Virginia Tech's David Wilson, both expected to be second-round picks, ran an unofficial 4.40.
The vast majority of the unofficial times have been around a tenth of a second faster than the "official" time released later by NFL.com through National Football Scouting.
As we've noted during the event, NFLDraftScout.com data shows Trindon Holiday's 4.21 in 2010 as the fastest Combine time since 2000.
UPDATE: Miller was able leapfrog to the head of the running back class when the "official" 40 times were posted by NFL.com, being credited with a 4.40, while Rainey and James were dinged .07 from their unofficial handheld times down to 4.45. San Diego State's Ronnie Hillman was also credited with an official 4.45 after having a first clocking of 4.41.