Dec 5, 2015; Waco, TX, USA; Baylor Bears defensive end Shawn Oakman (2) is introduced before the game against the Texas Longhorns at McLane Stadium. The Longhorns defeat the Bears 23-17. Mandatory Credit: Jerome Miron-USA TODAY Sports

League personnel will flood Lucas Oil Stadium to observe the 2016 NFL Combine, and eight prospects in particular have plenty to prove in Indianapolis.

On-field testing — especially the 40-yard-dash — is the key selling point for fans, but many franchises are looking forward to sitting down for interviews. A couple guys with supposed character issues will attempt to quell any concerns from prospective employers during the meeting.

The combine is merely a small part of the scouting process, but a player’s draft stock can fluctuate based on the results both on the turf and between the ears.

Connor Cook, QB, Michigan State

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Why wasn’t Connor Cook a team captain? Is he selfish? Can he lead a football team? All of these questions will last throughout the draft process and may linger while the Michigan State product adapts to the NFL.

The interview process will be crucial for Cook, who could sneak into the late first round but will likely be a second-round selection.

Cook’s easiest response to anyone questioning his leadership acumen is that he was one of 12 Spartans voted an “Eagle.” In an interview with Bruce Feldman of Fox Sports, former MSU offensive lineman Jack Conklin said only “Eagles” can be team captains, so Cook was still a leader.

Oh, and there’s that whole “being a quarterback” thing. Cook is pretty darn good — especially against the blitz — but inconsistency against standard pressure makes analysts hesitate to consider him a Day 1 starter.

Kenneth Dixon, RB, Louisiana Tech

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Running backs that double as receiving threats are valuable commodities in today’s NFL. For some reason, though, one of the best versatile prospects isn’t receiving much attention.

Kenneth Dixon attended Louisiana Tech, which helps explain the oversight. Still, he eclipsed the 1,000-yard barrier three times in college, caught at least 30 passes twice and scored 26 touchdowns or more in three seasons.

Although there isn’t much Dixon must or can prove at the combine to boost his stock, a strong all-around performance in testing, drills and interviews would solidify his place as a Day 2 option in the draft.

Duke Johnson and Jeremy Langford — third- and fourth-round selections in 2015, respectively — have already earned significant roles on their NFL teams. Don’t be surprised if Dixon fits a similar mold.

Kolby Listenbee, WR, TCU

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Someone get Kolby Listenbee into a pair of Adidas cleats, because his speed might be worth $1 million before draft night even arrives.

The speedster from TCU caught 71 passes for 1,350 yards and nine touchdowns during the last two seasons. Additionally, he ran a “wind-legal” 10.04-second 100-meter dash at the 2015 NCAA Championships.

A hip injury hampered Listenbee in 2015, though, so hopefully that doesn’t rob him of any quickness.

But Listenbee needs to prove straight-line speed isn’t his only elite attribute. If he doesn’t run well, the 6-foot-1, 183-pounder must perform well during positional drills that focus on route running and actually catching the ball.

Braxton Miller, WR, Ohio State

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Braxton Miller is a perplexing prospect. His potential is undoubtedly appealing because it’s nowhere close to being reached. But where do you draft someone who has played 13 games at a position?

After spending three years as a quarterback at Ohio State, Miller transitioned to wide receiver in preparation for the NFL. He dropped jaws with a highlight-reel spin in the season opener but didn’t really do much else while the Buckeyes put together an uninspiring year.

Then the Senior Bowl happened. A panel of scouts and Senior Bowl personnel voted Miller as the top practice performer during the week — of note, Dixon was considered the best running back.

NFL teams know Miller is explosive and has plenty of room to develop. But how does he compare to his best positional counterparts on the same field? We’ll find out at the combine.

Shawn Oakman, DE, Baylor

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You might not find a more physically imposing upper-body specimen than Shawn Oakman. During the Senior Bowl measured in at 6-foot-7 and 269 pounds — a shade smaller than his college listing, as per the usual.

But one question that remains is the explosiveness of Oakman, who might have skipped a leg day or seven. Another is how he’s matured since being kicked out of Penn State for stealing a sandwich and grabbing the wrist of the woman who immediately questioned Oakman.

Plus, he seemed to regress inside the white lines last season. His sack total dropped from 11 in 2014 to 4.5 as a senior, which is an alarming trend since opponents weren’t use triple-teams like they did on Ohio State’s Joey Bosa.

Oakman had better ace his interviews because the on-field test offers little more than a passing grade.

Noah Spence, DE, Eastern Kentucky

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The best prospect with the “character red flag” label is Noah Spence. He started his college career at Ohio State but failed multiple drug tests and finished at Eastern Kentucky.

Spence had 22.5 tackles for loss including 11.5 sacks last season. The 6-foot-3, 254-pound defensive end seems to have moved on from his previous issues, but a 2015 draftee with a similar history isn’t helping Spence.

Randy Gregory recently received a four-game suspension for, you guessed it, failing multiple drug tests. Spence can expect to hear a handful of questions about his missteps in Columbus.

Without a red flag, Spence could be considered a lock for the top five. He’ll need to convince a handful of teams those problems are in the past, because his on-field testing should bring results worthy of that high billing.

Scooby Wright, LB, Arizona

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Arizona linebacker Scooby Wright had a respectable freshman season with 83 total tackles, but he really turned heads as a sophomore.

The 6-foot-1, 246-pounder registered 100 solo tackles, adding 64 assisted stops for an NCAA-best mark of 164. Wright notched 15 sacks, which ranked third nationally. He won the Nagurski and Bednarik awards as well as being named a consensus All-American and Pac-12 Defensive Player of the Year.

But an injury stunted his progression. Wright missed most of the 2015 campaign due to a foot injury. One scout, per the Arizona Daily Star, said Wright is now a third-rounder at best.

Poor testing will drop him even more, especially if he moves slower than anticipated laterally. Sideline-to-sideline quickness is imperative in today’s NFL. Without that, a bunch of tackles in college won’t mean much.

LeShaun Sims, CB, Southern Utah

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Similar to Listenbee, LeShaun Sims is an absolute blazer. Unlike the TCU product, basically no one has heard of the Southern Utah cornerback.

Josh Norris of Rotowold admitted he hadn’t watched Sims prior to the East-West Shrine Game but left the practices impressed with the 6-foot-0, 201-pound speedster. He tallied 220 tackles, 25 pass breakups and eight interceptions while in college.

NFL teams must project how that production translates to competition two levels higher. Something they can compare, though, is his speed.

On your mark. Get set. Watch Sims fly — and maybe earn $1 million.