Penn State Faces Biggest Comeback Test of Season, Trails USC 20-6 at Halftime

The Trojans' Quinten Joyner scores two first-half touchdowns, including the longest against Penn State this season.

Penn State quarterback Drew Allar warms up prior to the game against the USC Trojans at Los Angeles Memorial Coliseum. / Jayne Kamin-Oncea-Imagn Images

LOS ANGELES | Penn State must rally from its largest deficit of the season to remain unbeaten, as the Nittany Lions trail USC 20-6 at halftime. Fourth-ranked Penn State gave up a series of first-half big plays, notably the longest touchdown scored against its defense this season, and couldn't score touchdowns on two trips into the USC red zone.

A look at Penn State-USC at the half.

USC's big-play offense

Penn State entered the game ranked second in the Big Ten in explosive-play defense, having allowed just 13 plays of 20+ yards through four games. USC generated four in the first half alone, three on the ground, to inside-out the Nittany Lions' defense.

Quinten Joyner's scored from 75 yards on a perfectly called and executed end around, while Woody Marks had runs of 21 and 28 yards to set up Joyner's second touchdown. As a result, the Big Ten's No. 2 rushing defense, which had allowed one 100-yard rushing game against its last 16 Big Ten opponents, gave up 147 yards rushing in the first half.

Drew Allar's second interception

Allar has protected the ball well this season, throwing just one interception, but his second came in a tough spot. On a second-quarter third down, Allar looked off a receiver left and threw right side to Liam Clifford. USC linebacker Desman Stephens II read Allar perfectly, undercutting the short ball for the interception. His 42-yard return (Clifford made the tackle) set up USC in terrific field position. But the Nittany Lions got a stop, with a key tackle for loss from cornerback AJ Harris, limiting USC to a 45-yard field goal to take a 17-3 lead.

Two pivotal plays of the first quarter

Penn State offensive coordinator Andy Kotelnicki scripted a show-biz offense on the opening series, mixing tempo, new formations, Vega Ioane in motion again and a ton of Tyler Warren. It was entertaining to watch but stalled inside the 5-yard line. The Nittany Lions ran once (a Drew Allar scramble) and had a touchdown pass from Allar to Warren called off by offensive pass interference (receiver Julian Fleming appeared to get his hands up too high).

Penn State's 3-0 lead, after Ryan Barker's 35-yard field goal, didn't last one play. Joyner dazzled on USC's next play from scrimmage, slicing through several overpursuing Penn State defenders to score from 75 yards. It was the longest play Penn State's defense has allowed this season.

Close calls

Penn State's offense was frustratingly close to two first-half touchdowns. Warren's first-half touchdown catch was taken off the board by Fleming's penalty. And in the second quarter, receiver Trey Wallace had a step on his coverage in the end zone and got his hands on Allar's pass but couldn't complete the catch. On the next play, Allar scrambled and looked for Warren, who wanted pass interference. He didn't get it, and Barker made his second field goal of the game.

Warren has made a huge impact, catching nine of Allar's 12 completions for 98 yards. He has 92 yards after contact.

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