This is a guy who is a great natural player, but just too high of a risk to take a chance on. I wonder if he'll even be drafted....

Reminds me A LOT of Vontaze Burfict from last year's draft:

"Vontaze Burfict was awful in every possible way at the NFL Combine last year.
He ran slower than any linebacker, jumped poorly, and failed his interviews with NFL teams.
The performance was so bad that he went undrafted despite being a consensus first-round pick last winter.
But in a twist that makes you question the value of the Combine, ultimately none of that mattered. He signed with the Bengals as a free agent, got promoted to starter early in the year, and was the team's best linebacker by the playoffs.
Burfict looked to be a total mess at this time last year, so it's unfair to criticize the writers who bashed him too badly.
But his story just goes to show yow how a Combine performance (good or bad) can be blown totally out of proportion.
Here's what people were saying about Burfict last year.
Bob Young, The Arizona Republic:
"He didn't even bother with the bench-press test or shuttle runs. So, let's see: No speed. No explosiveness. No competitive spirit.
"Yep, you want to invest millions of dollars in this guy."
Don Banks, SI, who gave him the "Career Self-Destruction Award":
"Burfict had a nice week. He proclaimed himself the "best linebacker in this draft,'' blamed everyone else but himself for his shaky 2011 season, defended his decision to "swing on'' a teammate in a locker-room fight last year, and then ran a disappointing 5.09 and broad-jumped just 8 feet, 7 inches. This is a guy who came across to the league as having blind spots the size of, well, the Grand Canyon, which coincidentally is in Arizona.
"Burfict thinks he's a misunderstood first-round talent. The league is more likely to give him an underachiever's third-round grade. And factoring in his winning personality and personal baggage, don't be surprised if you don't hear his name called on draft weekend until the third and final day."
Mike Mayock, NFL Network:
“I put his tape on with absolutely zero preconceived notions. I watched three tapes and really didn’t like him as a football player. I think he’s a non-draftable kid. For me, he’s a free agent.”
An unnamed NFL scout (via CBS Sports):
"I wouldn't touch him. He does have some talent, but he is so undisciplined on and off the field. The guy is completely out of control. There's no way you could trust him. I can't believe they (ASU coaching staff) didn't cut him loose."
ESPN Scouts Inc.:
"Burfict's 2011 film says he's a third-rounder, and when you add in those results along with character baggage and poor interviews his stock is beginning to plummet."


http://www.businessinsider.com/vontaze-burfict-shows-how-little-nfl-combine-matters-2013-2#ixzz2QLWSoOs6 

Burfict was regarded a head case, and too high of a risk to draft. But the kid has insane talent and wound up topping all players in the NFL's Performance Based Pay Program.

Mathieu, while a giant risk, has the football intangibles and instincts to become a great player. Any team that takes him or signs him as a UFA will be assuming almost the same kind of risk, and they may reap huge rewards. It is on this level a tough call.