Either you believed he was going to be the playmaker we all saw at LSU who finished fifth in the Heisman voting back in 2011, or you believed there was no way this vertically challenged, troublemaking Honey Badger would make an impact at the NFL level.
Despite suffering a knee injury that ended his first season with just three games left to play, Mathieu succeeded in silencing his doubters in a breakout rookie campaign.
A bittersweet ending to a fantastic season.
Looking back at Mathieu's rookie season
Those who believed in Mathieu all along knew the Cardinals got a steal when they selected him with the No. 69 overall pick. This was a guy many considered the best defensive player in college football just a season before, and the Cardinals were able to get him with a mid-round pick.
But even those who expected success from Mathieu couldn't have predicted the kind of season he had for the Cardinals defense.
According to the current Pro Football Focus grades (subscription required), Mathieu ranks as the No. 2 cornerback in the NFL.
|PFF's Top 5 cornerbacks (As of 12-19-13)|
|1||Darrelle Revis||Tampa Bay Buccaneers||17.3|
|2||Tyrann Mathieu||Arizona Cardinals||15.5|
|3||Brent Grimes||Miami Dolphins||13.6|
|4||Vontae Davis||Indianapolis Colts||13.2|
|5||Tramaine Brock||San Francisco 49ers||12.2|
|Pro Football Focus|
Last year it was Green Bay Packers rookie cornerback Casey Hayward who surprised a lot of people and finished as the No. 4-ranked cornerback in the NFL. Besides Mathieu and Hayward, no rookie cornerbacks have finished in the top five of PFF's grades since 2008.
Mathieu's success may have surprised a lot of people, but he wasn't one of them.
Even back in the preseason, before he had proven to everyone that he belonged on an NFL field, Mathieu spoke confidently about his abilities to the Cardinals' official website.
"The expectations can never amount to mine," Mathieu said. "I want to play a big role. Everybody always has something to say, whether it's good or bad. I just leave it at that and do what I do best, which is play football."
Those words signified more than just a player being confident about his abilities. Simply put, Mathieu had question marks hanging over him—widely documented issues during his time at LSU and his subsequent release from the program for violation of team rules.
For Mathieu to say, "I just leave it at that and do what I do best," signified maturity and an understanding of the position he was going to be in, and one that he'll continue to be in as a professional athlete.
He understands there's always going to be noise around him, yet the only thing he seems to be focused on is football. That's a sign of growth.
This growth might explain his ability to make an immediate impact for the Cardinals defense.
We all saw the talent as he took over college football back in 2011 playing at LSU. It was must-see TV anytime the Honey Badger was playing.
But the noise became too much for him back then and ultimately took him down a path we've all heard by now.
Mathieu's rise and fall at LSU
It didn't matter if you were an LSU fan or just a college football fan. Everyone knew who the Honey Badger was.
Mathieu reached that level of notoriety after a historic season at LSU back in 2011.
He won the Chuck Bednarik Award, given to the nation's best defensive player. He helped LSU win the SEC championship and led it to an appearance in the national championship game, where it ultimately fell to Alabama.
He was a Heisman finalist and All-American after scoring four touchdowns, two on punt returns and two on fumble returns. He also intercepted two passes and forced six fumbles. The 5'9", 175-pound playmaker had everyone's attention.
He reached that rare level of everyone always watching and expecting him to make a big play, and then he went out there and made that big play.
But a one-game suspension during that remarkable 2011 season because of a failed drug test might have been the writing on the wall. Less than a year later, LSU kicked him off the team for violations of team rules.
LSU coach Les Miles didn't spell anything out specifically but said, via Jim Kleinpeter of the Times-Picayune, "We have a simple policy here of behavior. Consequences are pretty (well) spelled out and defined. We did what we could do, but Tyrann is no longer on our team. He violated team policies."
A series of unconfirmed reports regarding Mathieu's off-field behavior continued to circulate after he declared for the NFL draft.
The noise had to be deafening for Mathieu. But he brought it on with the decisions he made, and for where he wanted to go, people would need answers.
Here's a player who proved to be a star on the field but consistently made bad decisions off the field. What was going to change when he received NFL money and freedom?
It was going to take the right fit and the right people around him for Mathieu to realize his potential—and stay there.
Luckily for him, that's exactly where he ended up.
Standing on the table for a friend
Former LSU cornerback Patrick Peterson was the No. 5 overall pick for the Cardinals back in the 2011 draft.
The connection between Peterson and Mathieu goes beyond simply being teammates together back at LSU.
When Mathieu needed to get away from Baton Rouge after being dismissed from the team, it was Patrick Peterson Sr., the former No. 5 pick's father, who opened his home. He and his wife counseled Mathieu as he prepared for the combine.
Peterson said of his relationship with Mathieu, via Terrance Harris of the Times-Picayune, "We're practically brothers. I feel that I'm the big brother, role model type for him."
Before the draft, Peterson had a conversation with Cardinals coach Bruce Arians about Mathieu, via that same article from Harris: "Patrick Peterson came in my office and said, 'Hey Coach, I'll stand on the table for this guy. Give him a chance.'"
Arians understood where Mathieu was coming from and what he was looking for. "He knew he messed up; we all mess up in life," Arians said. "It's time to give him an opportunity, and he's doing everything he can to make sure he does great with it."
It didn't matter how well Mathieu played in college or how many people vouched for him before he got an opportunity.
If Mathieu didn't perform when given that opportunity, it wouldn't matter.
But as we know, Mathieu did perform this season, and both Peterson and Arians look the better for trusting one another and believing in Mathieu.
Just how exactly did Mathieu fit into the Cardinals defense?
Let's take a look at how Mathieu switched between nickel corner and safety this season, showing versatility and the playmaking ability that earned him PFF's No. 2 ranking.
It didn't take long before Mathieu put his playmaking abilities on display this season. The video below is from the Cardinals' first game of the season on a play in the first quarter.
Mathieu is initially lined up as the nickel cornerback on the slot receiver. The St. Louis Rams run four verticals and hit the tight end, Jared Cook, on the seam route down the middle of the field.
Not giving up on the play, Mathieu chases Cook down and forces a fumble by diving and poking the ball out at the 5-yard line. These are the kinds of plays that gave Mathieu the Honey Badger nickname.
This next play might not end up in a highlight reel, but it could have very easily prevented a huge gain for the Texans offense and running back Ben Tate.
Mathieu is lined up in the nickel corner position (circled in red), and the running play is coming to his side of the field.
In the second photo you can see that he has two offensive players near him (3 and 4), while the other two offensive players are clearing out the defensive lineman attempting to disrupt the play.
There is plenty of room for Tate to make something happen in the open field when you look at that third picture. Mathieu has the white arrow pointed at him.
Not only does Mathieu split the two blockers to create an opportunity to make a play, he also closes in on Tate and brings him down before he can get into the open field.
Could the safety have made the tackle? Absolutely, but there's no denying Mathieu saved yards here; it's simply a matter of how many he saved.
There aren't a lot of nickel corners who make that play.
This final play is all about athletic ability.
The Cardinals are in their dime defense, and Mathieu is lined up in the box as a linebacker. He's going to be covering Colts tight end Coby Fleener, running the shallow cross across the middle of the field.
Whenever you hear the term "fluid hips" in regards to a defensive back's ability to turn and run in the open field, just think of this play.
Mathieu gets completely square to Fleener as he makes his move across the middle. This is a terrible position for a defensive back to be in based on the route that's being run.
It would be very simple for Fleener to create all kinds of space between himself and Mathieu as he crosses.
But Mathieu's ability to open his hips and accelerate instantaneously to keep up with Fleener is unbelievable. Mathieu knocks down the pass and is a half-count behind picking it off and taking it back for a touchdown.
Most other defensive backs couldn't recover from the position Mathieu found himself in once Fleener made his move.
But thanks to elite athleticism and playmaking ability, Mathieu made it look easy. That's a reason PFF ranked him the league's No. 2 cornerback.
These plays are just examples of the kind of versatility Mathieu brought to the Cardinals defense. He was able to step up in run coverage and get off blocks to make plays. That was one of the concerns about him transitioning to the NFL due to his size.
People weren't sure if he'd be able to handle the physical play inside the box. However, considering the Cardinals lined him up all over the field, including in the box in their dime defenses, he answered those questions.
Overcoming new challenges
Mathieu proved a lot of people wrong with the way that he played this season.
He accepted the challenge of making his opportunity all about football, and he said as much to Arians back when they drafted him.
Now he's faced with a new challenge: overcoming a knee injury and going through the rehab process.
It's still up in the air if he'll be ready for the start of the 2014 season.
That said, anyone doubting whether Mathieu can come back as the same player doesn't have to look any further than the cornerback ranked higher than Mathieu in PFF's rankings.
That would be Tampa Bay Buccaneers cornerback Darrelle Revis, who overcame a torn ACL last season to come back and play at a high level this year.
It was a bittersweet end of the season for Mathieu, who played at a level higher than most expected but still won't get the benefit of the doubt moving forward now that he's coming off an injury.
Maybe we could learn something from Mathieu and avoid our past mistakes, because anyone doubting him at this point should be drug-tested.