The biggest factor in the College Football Playoffs is the health of Alabama quarterback Tua Tagovailoa.
The Heisman Trophy finalist has proved his value throughout the season, as he has given Alabama a sophisticated and high-powered passing attack to go along with the hard-hitting defense and power running game they have been known for over the years.
Alabama head coach Nick Saban is hopeful that Tagovailoa will be in the lineup when the Crimson Tide meets Oklahoma in the national semifinal game. Tagovailoa suffered an ankle injury in the SEC title game against Georgia, and he underwent a procedure that will take about two weeks to recover.
"I think Tua's right on schedule," Saban said, per Andrew Olson of SaturdayDownSouth.
If that assessment is correct, Tagovailoa will be able to practice and prepare for the game. If it is not, Saban will have to turn to backup Jalen Hurts, who led the Crimson Tide to a come-from-behind win over the Bulldogs and allowed Alabama to hold on to its perfect season.
National College Football Semifinals
Matchup: No. 3 Notre Dame vs. No. 2 Clemson
Date: December 29
Bowl Game: Cotton Bowl, AT&T Stadium, Arlington, Texas
Time: 4 p.m. ET
Matchup: No. 4 Oklahoma vs. No. 1 Alabama
Date: December 29
Bowl Game: Orange Bowl, Hard Rock Stadium, Miami Gardens, Florida
Time: 8 p.m.
Notre Dame vs. Clemson
The Tigers have been chasing Alabama as the nation's No. 2 ranked team throughout the season, and if Clemson (13-0) can beat Notre Dame (12-0) here, they will likely face the Crimson Tide for the national championship.
The experts see Clemson getting past Notre Dame, as the Tigers are favored by 11.5 points, per OddsShark.
Despite the big point spread, don't expect Notre Dame to have any fear when it takes the field at AT&T Stadium.
The Fighting Irish have answered every challenge to this point, and they have the kind of skill on offense and tenacious defense that should cause a lot of problems for Clemson.
Quarterback Ian Book is a sharp passer and has completed 197 of 280 attempts for 2,468 yards with 19 touchdowns and six interceptions.
He has two excellent receivers in Miles Boykin and Chase Claypool who can both make big plays down the field and have shown run-after-the-catch ability.
Boykin has caught 54 passes for 803 yards and eight touchdowns, while Claypool has 48 receptions for 631 yards and four scores. Running back Dexter Williams can take advantage of any defense that overplays the pass, and he has rushed for 941 yards and has scored 12 times.
The Tigers are probably more explosive than Notre Dame with quarterback Trevor Lawrence leading their high-powered attack.
Lawrence has thrown for 2,606 yards, and he has a razor-sharp 24-4 TD-interception ratio. He also has a tremendous asset in running back Travis Etienne, who has gained 1,463 rushing yards and scored 21 touchdowns while averaging 8.3 yards per attempt.
Tee Higgins is Clemson's most productive receiver with 52 receptions for 802 yards and 10 touchdowns, while Justyn Ross has 34 receptions for 699 yards and six scores.
Look for Notre Dame to battle Clemson on even terms well into the second half. The Irish will gain confidence as the game goes along, and Clemson may start to have doubts when they don't put the Fighting Irish away.
Notre Dame wins this game on a late field goal from Justin Yoon, who has made 16 of 20 three-pointers to this point in the year.
Oklahoma vs. Alabama
This game has all the trappings of a college football classic, at least from an offensive perspective.
Tagovailoa will lead the Alabama (13-0) offense if he is healthy enough to go, and Hurts is a superb quarterback in his own right. He started last year's national championship game before giving way to Tagovailoa, and he is a smart leader. Hurts has thrown for 755 yards with eight touchdowns and two interceptions in limited action.
Oklahoma (12-1) quarterback Kyler Murray has had a spectacular season for the Sooners. He has 4,053 passing yards and has completed 70.9 percent of his passes. Murray has thrown 40 scoring passes with seven interceptions and has rushed for 892 yards and 11 touchdowns.
Murray will join Tagovailoa in New York as a Heisman Trophy finalist.
Wide receivers Marquise Brown and CeeDee Lamb are Murray's favorite targets. Brown has caught 75 passes for 1,318 yards and 10 scores, and Lamb has 57 receptions for 1,032 yards and 10 TDs.
Tagovailoa is a brilliant player when he is healthy. He has thrown for 3,353 yards with 37 touchdowns and four interceptions.
Jerry Jeudy is the most productive of his receivers, catching 59 passes for 1,103 yards and 12 touchdowns. He was named the winner of the Biletnikoff Award as the nation's best receiver Thursday night.
Jeudy is joined by Henry Ruggs III, Jaylen Waddle and Irv Smith Jr. That trio of receivers has caught 121 passes that have resulted in 24 touchdowns.
The big issue in this game is the lack of defense played by the Sooners. Oklahoma gave up 40 or more points in four straight games prior to the Big 12 title game, and Alabama could crack the 50-point mark against this team.
Alabama is a 14-point favorite, and while Oklahoma may be able to stay with the Crimson Tide into the second quarter, the Sooners defense will cave in during the third and fourth quarters.
Alabama wins and covers the spread, setting up a national championship game between the Fighting Irish and the Crimson Tide.