What awaits Penn State in its playoff test with SMU? Here’s the rundown on the high-scoring Mustangs.

Southern Methodist endured quite a few changes early in this football season, its first in the Atlantic Coast Conference, but that did not stop the Mustangs from reaching the ACC title game.

The Mustangs were picked to finish seventh in the ACC in the preseason coaches’ poll. Now they stand at 11-2 and are heading for their first College Football Playoff appearance. Eleventh-seeded SMU will make the trip to Happy Valley to face sixth-seeded Penn State (11-2) on Dec. 21 at noon (TNT/Max).

The former American Athletic Conference team looks different than it did this summer at a few key positions. For starters, the Mustangs’ quarterback, Preston Stone, was benched in favor of backup Kevin Jennings during a loss to Brigham Young on Sept. 6. Their top returning receiving target, tight end R.J. Maryland, suffered a season-ending injury in October, but Miami transfer Brashard Smith triggered a nine-game winning streak by elevating the running game.

Although preparations for both teams are in the early stages with a week off before their first-round matchup, here’s a look at what makes this SMU squad difficult to stop on offense — led by Jennings — and how its defense confuses opposing offenses.

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Mustangs coach Rhett Lashlee revealed earlier this week that Jennings has played through a broken finger on his left hand he suffered during an overtime win against Duke on Oct. 26. But that hasn’t slowed him down this season, as Jennings has accounted for more than 3,400 yards and 27 touchdowns to lead the No. 7 scoring offense and No. 20 passing offense in college football.

What makes him particularly difficult to game-plan against is his ability to extend plays outside of the pocket with running ability that forces defenses to account for schemed quarterback runs. Teams have put one fewer player in coverage in an attempt to keep Jennings within the confines of the pocket.

SMU runs an up-tempo style offense that mirrors what Penn State saw against Oregon in the Big Ten title game. The Mustangs crank up the pace, especially after picking up first downs, to keep defenses off balance. That type of tempo gave the Nittany Lions defense issues as they gave up 31 first-half points to the Ducks on Saturday. The Mustangs aren’t afraid to attack defenses in the vertical passing game, often dialing up throws downfield a handful of times in a quarter to keep defenses honest while attempting to exploit man coverage.

Meanwhile, Smith has rushed for 1,270 yards and averages 5.9 yards per carry. He has excellent vision and patience as a runner to help set up the blocks in front of him. SMU utilizes his decisive running style with zone runs, power and counter run-schemes that test opposing linebackers’ discipline.

Then there is Jennings’ running ability (379 rushing yards), which forces defenses to always have eyes on him on potential zone read runs. Smith is used as a receiver out of the backfield, too — he has 35 catches and four receiving touchdowns this season — and is used in motion across formations to set up outside runs or quarterback runs into the teeth of the defense.

One player the Nittany Lions defense will need to contain on the outside is versatile wideout Roderick Daniels Jr., whom the Mustangs utilize in the backfield as another runner and in the slot matched up with safeties and nickel corners. Daniels is small in stature (5-foot-9, 186 pounds) but is their main vertical threat. He has 81 total offensive touches (43 carries, 38 catches) and has accounted for 762 yards and seven touchdowns (three rushing, three receiving, one punt return). He’s also the team’s primary punt returner.

But a weak point of the SMU offense is its pass protection, specifically on the left side of the line. Left tackle Savion Byrd has struggled at times this season. According Pro Football Focus, Byrd, an Oklahoma transfer, has allowed two sacks, 16 quarterback pressures, and committed nine penalties this season. Penn State’s pass rush is the strength of its defense, and Byrd’s struggles should allow pass rushers Abdul Carter and Dani Dennis-Sutton to create backfield pressure on Jennings.

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Operating in a 4-2-5 defensive scheme (four defensive linemen, two linebackers, five defensive backs), the SMU defense relies on disruption from its front four. Led by defensive end Elijah Roberts, the Mustangs have five players with more than four sacks this season. Edge rusher Jahfari Harvey has 12 tackles for losses and seven sacks, the team leader in both categories, while Roberts has 5½ sacks. As a team, the Mustangs ranked 11th in college football with 3.1 sacks per game and tied for the third-highest sacks total with 40.

The up-front disruption has allowed the Mustangs to stifle the run, too. SMU has the No. 4 rushing defense nationally, giving up only 93.4 yards per game, with its 2.7 yards per carry average ranking third. The penetration by players like Harvey and Roberts keeps Mustangs linebackers Kobe Wilson and Ahmad Walker free to make run stops. Penn State’s running back duo of Nick Singleton and Kaytron Allen will play a big role in trying to break that trend next weekend.

The strong pass rush allows SMU to play more zone coverage on defense in an effort to eliminate downfield throws outside the numbers. Although the Mustangs rank in the bottom third in pass defense, SMU’s third-down defense ranks inside the top 20, allowing teams to convert at a 32.3% clip. In addition to getting off the field on third downs, the Mustangs disguise their coverages, aided by the effectiveness of their pass rush, which has forced opposing quarterbacks into inaccurate or rushed throws into the teeth of the defense.

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Safeties Isaiah Nwokobia and Ahmaad Moses will be tested by Penn State tight end Tyler Warren over the middle of the field. Nwokobia and Moses both have three interceptions this season, with Nwokobia allowing an NFL passer rating of 69.4 when targeted while Moses has a 68.5 rating, according to Pro Football Focus.

The Mustangs defense is most vulnerable on the perimeter and up the seams, the typical weaknesses of a zone defense. If Penn State quarterback Drew Allar can find those openings and get into a nice rhythm, assuming his protection holds up, the Nittany Lions offense could find major success against an SMU defense that has allowed 400 yards of offense in four games this season.