FORT LAUDERDALE, Fla. -- No matter your allegiance or perspective on the College Football Playoff selections, no matter your opinion of Oklahoma's worth or boredom of Alabama's dominance, Saturday night's semifinal game between the two is a matchup for the ages. No. 1 Alabama enters the Orange Bowl against No. 4 Oklahoma as a 14-point favorite, a massive line for a semifinal game. But the game also pits the nation's two best offenses against each other, both historic in their productivity. It pits the Heisman Trophy winner against the Heisman Trophy runner-up. It pits football's best coach against a rising star.  

Here are five keys that will determine if a matchup for the ages translates into a game for the ages when the Orange Bowl kicks off on Saturday night at Hard Rock Stadium in Miami Gardens.

1. Tua Tagovailoa's health: Since the last time we saw Tagovailoa in the SEC Championship Game, he has undergone a surgical procedure on his ankle and taken part in intensive rehab to get ready for this game. Asked about his health status on Wednesday, Tagovailoa said, "If I could grade it on a scale of 0 to 100, I'd probably say it's about 80 to 85 percent. It's been really good." Tagovailoa went on to say that he expects to be at 100 percent by kickoff.

The accuracy of those statements may be a determining factor in this game, if not the determining factor. While he's had a lingering knee issue most of the season, we've really only seen two games this season in which Tagovailoa has looked significantly bothered by injury: Mississippi State and Georgia. In those two games, a quarterback that has completed 68 percent of his passes on the year and thrown 37 touchdowns to only four interceptions completed a combined 51 percent of his passes for two touchdowns and three interceptions.

Tagovailoa is not a dual-threat quarterback in the traditional sense of the term. Alabama isn't going to scheme up a gameplan around him being a primary ball-carrier, but his mobility is an integral part of his success. His pocket movements, ability to evade pass-rushers and playmaking instincts are all tied to his mobility. If those things are muted by a lower-body injury, we see a different version of Tagovailoa and a different version of Alabama that Oklahoma would much prefer.

But the Sooners aren't a passive participant in this. The reason Tagovailoa was banged up against Georgia and Mississippi State was due largely to those two programs making him uncomfortable, creating pressure and forcing him to react quickly and test his knee and ankle. If Alabama's offensive line can keep Tagovailoa clean, his health status may not matter.

2. Ball security for Bama: Oklahoma's defense is ranked No. 100 in yards per play nationally. But it also doesn't really matter how many yards the Sooners give up, it's about how effectively can it get the ball back to the offense. The more discouraging stat for Oklahoma fans is that the Sooners are No. 121 in the nation in takeaways. But here's the good news. That defense has made plays when it has mattered.

Against Army, Oklahoma had a fourth quarter interception to end a 17-play drive that could have resulted in a game-winning score. It also intercepted a pass in overtime to seal the win. In a ping-pong matchup against Oklahoma State, Kenneth Murray recovered a fumble in the fourth quarter that ended a promising drive for the Cowboys which the offense promptly converted into a game-winning scoring drive the other way. Against West Virginia, the defense gave up 56 points and 704 yards but scored twice on fumble recoveries, proving to be the difference. In the Big 12 Championship Game a fourth-quarter safety and interception delivered the win.

We've also seen what it looks like when Oklahoma doesn't get a critical turnover in a shootout. In the Red River Rivalry, Lincoln Riley's offense put up 45 points and 532 yards of offense, but the defense couldn't force a turnover and gave Texas the breathing room it needed to pull a three-point upset.

Fortunately for Alabama, it has been outstanding taking care of the football. It's No. 13 in the nation with only 13 turnovers lost on the year. But turnovers are random and unpredictable. Oklahoma needs some chaos because if the Tide don't lose any possessions to turnovers, it's hard to see the Sooners defense being able to hold up.

3. Winning the third phase of the game: One of the few clear advantages Oklahoma has in this game is in the special teams department. According to S&P+, Oklahoma has the No. 32 special teams unit in the country. Alabama is ranked No. 93 in the same category. It's the only real flaw on this Alabama team and even that imperfection is laced with the electricity of freshman Jaylen Waddle as one of the nation's most dynamic return men.

Alabama has missed eight extra points this season. Oklahoma has missed one and placekicker Austin Seibert is seven points away from setting the all-time scoring record in college football by a kicker. Oklahoma averaged 39 net yards per punt, good for No. 34 in the country. Alabama is No. 116 in the same category.

For special teams to matter, Oklahoma has to play at a really high level everywhere else but if it gets late and the game comes down to a kick one way or the other, the Sooners can feel good about their guy.  

4. The line of scrimmage: Alabama under Nick Saban has been defined by dominance in the trenches: talented running backs behind a huge offensive line and an immovable object on the defensive front eating up blockers for speedy, nasty linebackers. That hasn't changed with this team, but now it has also added a dynamic quarterback and a bevy of weapons at receiver that we haven't seen before. Ultimately though, the line of scrimmage still decides this game.

If Alabama can dominate the line of scrimmage, manipulate pace, keep its quarterback upright and gash the Sooners in the run game, it's hard to envision Oklahoma figuring out a way to victory. So, Oklahoma needs guys like true freshman defensive end Ronnie Perkins to come of age and have some breakthrough moments to give its secondary a chance. It also needs guys like Neville Gallimore and Amani Bledsoe to be as stout and disruptive as they've ever been at the point of attack.

On the Oklahoma side, this is not just your traditional spread offense with a finesse identity. It's anchored by an offensive line that just won the Joe Moore award handed to the best offensive line unit in the country. It's a physical and nasty group, two traits Alabama prides itself on defensively. Alabama has a top 10 lock in the NFL Draft in defensive lineman Quinnen Williams and he's joined by some massive buddies in Raekwon Davis and Isaiah Buggs. Something has to give.

5. Kyler Murray's performance of a lifetime: If Oklahoma is to have a chance, Kyler Murray has to be at his best. This is non-negotiable. All year long, there has been no margin for error for Murray. That's the single most-compelling case for his Heisman victory: he couldn't afford an off day. He certainly can't afford an off-day against Alabama.

Alabama looks like a better football team. It is inarguably a more balanced football team. But Oklahoma is averaging 8.8 yards per play, the best per play average in modern college football history, and all of that productivity runs through Murray. If Alabama struggles, it wouldn't be the first time a mobile quarterback gave Saban fits. But mobile quarterbacks don't always give Alabama trouble, it just happens to be a pre-requisite.

We've seen quarterbacks elevate their teams on a stage like this before, whether it was Deshaun Watson at Clemson against Alabama or all the way back to Vince Young at Texas against the Alabama of the era, USC.  

This game may just be as simple as this: Can Kyler elevate Oklahoma, and can Kyler outduel Tua?