Justin Blackmon widely was criticized when he chose not to run the 40-yard dash during the NFL Scouting Combine in Indianapolis because of a hamstring injury. Mike Mayock of NFL Network reports Blackmon ran unofficial times of 4.48 and 4.49 seconds at his pro day, putting to rest any concern that he’d post a slow time in the 40. Blackmon is Mayock’s top-ranked wideout in April’s draft. Source: The Redzone
doesn't mean much. we don't need this big guy to run as fast as megatron and still make an impact. jerry rice's 40 time was never great either.