Derrick Henry at Alabama Pro Day 2016: Photos, Video Highlights and Reaction

A who's who of NFL personnel arrived in Tuscaloosa, Alabama, to see Alabama's pro day in person on Wednesday. Since his participation was limited, reigning Heisman Trophy winner Derrick Henry did little, however, to bolster his 2016 NFL draft stock.    

Center Ryan Kelly, defensive linemen A'Shawn Robinson and Jarran Reed, linebacker Reggie Ragland and quarterback Jake Coker were among the Crimson Tide players who took part in the showcase. According to Derrick Ansley, Alabama's defensive backs coach, every NFL team had at least one representative at the pro day:

Even New England Patriots head coach Bill Belichick made an appearance, per SEC Network:

A lot of eyes were on Henry, but he opted against running the 40-yard dash and participating in any individual drills, per Bleacher Report's Christopher Walsh.

Despite his impressive college career, there are significant question marks regarding Henry's NFL ceiling.

According to Sports-Reference.com, his 395 carries in 2015 are the fifth-most in Division I/FBS history. With a workload like that, it's fair to wonder whether his best football is still down the road.

Alabama also has a recent track record of producing great college running backs who fail to repeat their previous success at the next level. The jury is still out on T.J. Yeldon since he's only one year into his NFL career. But Trent Richardson is one of the bigger draft busts of the last few years, and Mark Ingram has largely been a disappointment outside of his 2014 Pro Bowl season.

NFL Network's Mike Mayock (via College Football 24/7) doesn't see Henry as a first-round prospect, which he argues is less about Henry's talent:

Tide head coach Nick Saban offered a defense of his former player, per Yahoo Sports' Eric Edholm, citing NFL Network, and CBSSports.com's Will Brinson:

Henry was never much of a pass-catcher at Alabama. In his three years at the school, he had 17 receptions for 285 yards and three touchdowns. He looked like a natural, though, during Wednesday's positional drill, via RosterWatch:

While he skipped most of the workouts, Henry made sure he made his presence felt. The Crimson Tide star was constantly motivating his teammates. NFL Network shared a clip of him pushing wideout Richard Mullaney to get one more rep on the bench press.

Henry also helped time Mullaney on the three-cone drill, via Alex Byington of the Decatur Daily:

While he didn't put his running skills on show, the incoming rookie flashed an impressive arm, per AL.com's Michael Casagrande:

Casagrande also shared a photo of Henry talking with a New York Giants representative:

According to NFL.com's Chase Goodbread, he also had one-on-one interviews with the New England Patriots, Cleveland Browns and Miami Dolphins on Tuesday.

On one hand, by running at Alabama's pro day, Henry could've potentially improved upon his 4.54-second 40-yard dash at the NFL Scouting Combine in Indianapolis. His 7.20-second time in the three-cone drill wasn't otherworldly either.

Then again, anything short of a sub-4.5 40 probably wasn't going to blow NFL personnel away and make him a surefire first-rounder. And there's almost no chance Henry could shave that much time off his combine mark.

Realistically, there's little else Henry can do to improve his draft position at this stage of the process. He ran for 2,219 yards and 28 touchdowns, won a national title and captured the most prestigious individual award in college football. His record on the field speaks for itself.

Whether he's selected in the first or second round, Henry is still on pace to be one of the top running backs off the board next month.