Two of the nation’s top defenses square off with a national title shot on the line.

Goodyear Cotton Bowl – College Football Playoff Semifinal

December 31, 8 p.m. ET (ESPN)

No. 3 Michigan State (12-1) vs. No. 2 Alabama (12-1)

How They Got Here

Michigan State upset Ohio State and then engineered a 22-play drive in the waning minutes of the Big Ten title game against Iowa to secure the Spartans’ second conference title in three years and a spot in the playoffs. After an early season loss to Ole Miss, Alabama steamrolled its next 10 opponents by an average of almost 22 points per game en route to a playoff spot and the Crimson Tide’s third SEC title in four years.

When Michigan State Has the Ball

Probably the biggest question mark going into this game is the health of Michigan State quarterback Connor Cook. The Spartan’s career passing touchdown leader suffered a shoulder injury against Maryland in mid-November. He missed the Spartans' next game against Ohio State and appeared to re-aggravate the injury in the Big Ten title game. Cook, who needs just 148 yards to pass Kirk Cousins as the school’s all-time passing leader, insists his shoulder is 100% healed and that he’s ready to go. But Alabama leads the nation in sacks and would like nothing more than to get to Cook early and put the health of his shoulder to the test.

Although Michigan State has shown that the running game can carry the team (most notably in the upset of Ohio State and in the Big Ten Championship), asking a one-dimensional offense to take down an Alabama squad that leads the nation in rush defense is a tall order. Connor Cook is going to have to play well for the Spartans to come out with a victory.

When Alabama Has the Ball

When the Crimson Tide takes the field, you know exactly what you’re going to get—all the Derrick Henry you can handle. The bruising Heisman winner led the nation in rushing yards (1,986), breaking Herschel Walker’s SEC single-season rushing record in the process. But he also led the nation in carries (339) and seemed to get better as each game wore on. Down the stretch of the season, Nick Saban put the Crimson Tide on Henry’s back, giving him 90 carries in the final two games against Auburn and Florida. While Alabama’s passing game has been efficient and perhaps underrated, there is no question that this is Derrick Henry’s team.

It will be a fun matchup to watch Henry take on a Michigan State defense that, playing in the Big Ten, has seen its share of pounding running backs. The Spartans rank ninth nationally in rush defense. Michigan State has given up just two rushing touchdowns in its last four games and opponents are averaging less than 3.2 yards per carry during that stretch. While Henry will still grind out yards, this is the best run defense that he will face this season.

Keys to the Game

If you’re a “defense wins championships” kind of person, this will be the game for you as two of the nation’s top defenses square off. Alabama is second in total defense and third in scoring while the Spartans, ranked 20th in scoring defense, have been dominant of late, giving up an average of just 12.5 points per game since early November.

Points will be at a premium in this one. We know that Derrick Henry will get plenty of carries to rack up some yards. And we know that Connor Cook will have some success in the air. So the real key to this may come down to the less heralded offensive playmakers. A big play from the Michigan State running game or from Alabama quarterback Jake Coker could decide this one.

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