Dan Wolken

USA TODAY Sports

ARLINGTON, Texas — Roughly 90 minutes before kickoff back on Sept. 19, word began filtering through Bryant-Denny Stadium that Alabama was going to make a quarterback change. Cooper Bateman was in and Jake Coker, the assumed starter who had yet to fully win the confidence of Alabama's coaching staff, was out for a game against Ole Miss that would become the crossroads of the Crimson Tide's season.

Given what was at stake for Alabama, it was a shocking decision. And Coker, as he now acknowledges, was not happy about it.

But the plain fact was that Coker had not yet settled the central issue in Alabama's season, even as coach Nick Saban was practically beginning him to. As a graduate transfer who came from Florida State with a lot of hype in 2014 but lost the job to Blake Sims and hadn't grabbed ahold of it two games into 2015, it was only natural to wonder if he ever would.

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"You could see it in his body language (he was disappointed), which is great," offensive coordinator Lane Kiffin said earlier this week. "I said that to him: We don't expect you to agree with this decision. If you agree with it, you're not competitive. We expect you to go prove it wrong, and he did exactly that."

Though Alabama lost that night and generally played a mess of a game, its late comeback with Coker at quarterback was the turning point of the season. Coker had proven to be Alabama's best, and perhaps only, legitimate quarterback option. Whatever direction this Alabama team was going to take, there was no more revolving door: After an entire spring and fall camp of uncertainty, it was finally Coker's team.

It would have been impossible for anyone to know that Alabama's trajectory from there to here, a 38-0 victory against Michigan State in the College Football Playoff semifinals, would have happened not in spite of its quarterback play but largely because of it.

Even as Alabama's largely drama-free season dragged along and Coker looked more and more solid, limiting mistakes while occasionally hitting a backbreaking big play, there was rarely a suggestion he was capable of being spectacular. With Alabama's dominating defense and Derrick Henry rushing for more yards than any back in SEC history, would there really be any need?

But as Alabama evolved from the night of the Ole Miss game into the team that made a mockery of Michigan State in the College Football Playoff semifinal on Thursday, Coker may have changed the entire perception of his brief tenure as Alabama's quarterback. When history looks back on the Crimson Tide's 38-0 victory against the Spartans, the most (perhaps only) memorable thing will be the way Coker outplayed Michigan State's Connor Cook.

"I wasn't surprised at all by the game he had tonight," Saban said. "He's pretty much done a good job all year long in terms of whatever we've asked him to do. Tonight he had to make plays because they were there, and he certainly made them. But I think in each game that we've asked him to do that, he's come through for us very nicely."

Even at Coker's best this season, it would have been hard to envision him doing what he did to Michigan State. The Spartans were committed to stopping Henry — which they did, limiting him to 75 yards on 20 carries — and basically told Alabama that Coker would have to make them pay. He did, completing 25-of-30 passes for 286 yards and two touchdowns. That accuracy helped the Tide to the best completion percentage (80.6) of any team in the five Playoff games that have been played.

"I knew it was going to come down to the receivers and quarterback: Could they make big plays?" Alabama receiver ArDarius Stewart said. "They were going to obviously try to stop Derrick and they did a good job stopping the run, but I knew on the outside they couldn't handle it. Jake performed excellent. 25-of-30? That's unbelievable."

It was evident from the opening drive that Michigan State was committed to its plan defensively and Saban/Kiffin weren't surprised. Instead of force-feeding Henry, who didn't touch the ball on the first drive, Alabama called run-pass option plays that required Coker to read what Michigan State was doing in the box and then get the ball to wherever Alabama had the numbers to block.

It ended up with Alabama going largely to the perimeter, nickel and diming its way down the field, until the bigger plays started to come. First to freshman Calvin Ridley, then to tight end O.J. Howard, and then pretty much to whomever and whatever Alabama wanted.

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"I think they were softening us up on the edge with a lot of quick routes outside and some screens," Michigan State coach Mark Dantonio said. "It's a catch-22 situation."

But for all Alabama's talent — and make no mistake, Alabama had the edge at basically every position on the field — the quarterback still had to deliver. And Coker, a fifth-year senior, has never been better in a more meaningful spot.

Teams are living organisms, always changing and mutating. For much of this season, Alabama was one-dimensional offensively, even if that dimension was hard to stop. Now, the Crimson Tide heads to Arizona looking like so much more.

"I felt they loaded the box a lot and our passing game would be open," Howard said. "Down the field, vertically was open on a lot of plays and we made it happen. We executed plays that were called. That's what you need out of your team when the running game isn't going well. You have to be able to throw the ball. Jake played great, our receiver made plays and thats what you need to go win a championship."

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