Reggie McKenzie on hand as Khalil Mack runs blazing fast 40-yard dash at Pro Day

The Scouting Combine is over and college Pro Days have begun. One Pro Day many NFL scouts are interested in is being held at University of Buffalo where top prospect Khalil Mack is working out today. The Raiders are interested enough to have the head man himself, Reggie McKenzie giving Mack a firsthand look.

Reports are good as Mack seems to have improved upon his official combine 40-yard dash time considerably. Several reports have Mack running a 4.54 40-yard dash today with ESPN's Adam Schefter reporting that one GM hand timed Mack at 4.45.

Going with the 4.54 time, that would put Mack in the top four among linebackers and defensive ends at the scouting combine right under Jadeveon Clowney who ran an official 4.53 at the combine. For Mack, that is an improvement of over a tenth of a second over his official 4.65 40-yard dash time at the combine.

His 40 time was the primary area he wanted to improve upon from the combine. He was already among the top performers in the 20-yard shuttle (4.18), vertical jump (40), broad jump (10'8") and bench press (23) -- all better numbers than Clowney turned in.

Mack is widely seen as the next best pass rushing prospect behind Clowney. Some analysts such as Mike Mayock actually have Mack ahead of Clowney due to Clowney's character concerns.

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