Kevin Sumlin vs. Bobby Petrino! The Music City Bowl might be a ... defensive struggle?

When you sign two five-star quarterbacks in two recruiting classes, you expect that the guy who doesn’t end up starting might leave. Losing both guys within a week is unique.

Kyler Murray is off to Oklahoma. Kyle Allen is off to somewhere. And the new starter is a guy named Jake Hubenak.

Hubenak averaged more than 500 passing yards per game at Cam Newton’s junior college. He might not have the physical gifts blessed to Murray and Allen, but he’s been a part of high-quality play. And honestly? A&M’s offense isn’t going to be much worse in Nashville than it was in the rest of 2015.

A&M’s profile is the opposite of what you would expect from a team that’s recruited at a top-10 level. The run game was efficient with almost no big-play threat. The passing game, led by two blue-chip quarterbacks and a host of former star recruits at receiver, was doomed by inefficiency and didn’t produce enough big plays to overcome that. A&M was mediocre on standard downs (49th in Standard Downs S&P+) and below average on passing downs (77th in Passing Downs S&P+).

This is worst offense Kevin Sumlin has been a part of since either the year Case Keenum got hurt at Houston or ever. It’s not a bad offense, but it takes on an underdog profile, one without enough big-play potential to succeed. So maybe this is an offense that an underdog recruit is suited to run.

If the A&M offense can relax and execute under Hubenak, the A&M defense might be able to stop Louisville enough to get a win. John Chavis’ first A&M defense improved to a healthy 30th in Def. S&P+; the run defense is still limited (82nd in Rushing S&P+), but the pass defense is downright awesome (second in Passing S&P+). A&M might not need to score much to win.

Bobby Petrino planted the seeds for a major breakthrough at Western Kentucky. He was only there for one 8-4 season before taking the Louisville job, but his successor and former coordinator Jeff Brohm produced the Hilltoppers’ first bowl win in 2014, then broke through with 12 wins and top-25 votes in 2015.

WKU is producing all of the points and yards we have come to expect from a Petrino offense. Louisville isn’t.

Petrino inherited young personnel from Charlie Strong and produced a No. 49 Off. S&P+ rating in 2014. And with freshman Lamar Jackson taking the most snaps at quarterback, it was perhaps an even younger offense in 2015 and ranked 50th. That’s a decent achievement. But we’ve come to expect more from Petrino, yes?

With defensive coordinator Todd Grantham’s rebuilt defense performing at a top-25 level (22nd in Def. S&P+), we’d have just assumed the Cardinals would have a top-30 offense to match, right?

Instead, Louisville has a top-25 defense, a top-25 run game (24th in Rushing S&P+), and a passing game that has dragged the Cardinals down. Jackson was a key piece of a fun, all-or-nothing run game -- he averaged 7.8 yards per non-sack carry -- but he took sacks on one of every 10 pass attempts and completed 56 percent of his passes with 10 touchdowns to eight interceptions. Predictably, the Cardinals were good as long as they could stay on schedule, but passing downs didn’t tend to go well.

Against an A&M defense so good against the pass (and so good at rushing the passer), that probably isn’t going to change in Nashville.

Louisville’s strengths and inefficiencies have combined to make every game close. In 11 games against FBS competition, the Cardinals only lost one game by more than 11 points and only won one by more than 14. They barely lost to ACC champion Clemson and beat a good NC State on the road; they also beat Wake Forest and Virginia by a combined eight.

If nothing else, they’ve gotten a lot of experience maneuvering in close-game situations, and maybe that pays off down the line. This looks like yet another tight matchup.

Check out the monstrous stat preview here.

Both defenses hold advantages on standard downs, and both offenses are pretty bad on passing downs. So ... if one offense is able to stay on schedule, that will probably determine the game.

With Hubenak, A&M might be able to surprise when the Aggies have the ball. He seems like a combination of potential and absolutely no FBS game film, and if A&M can create a temporary efficiency advantage, that might make the difference.

Meanwhile, assuming Louisville running back Brandon Radcliff is healthy (he injured his ankle against Kentucky), he and Jackson could combine to break off enough big runs to take the lead and keep passing out of the equation as much as possible. This offense may be limited, but an early start -- both in the game and in a given set of downs -- could go a long way.