It was the beginning of a new era for both USC and LSU, but only one of them got off to an ideal start.

Miller Moss, who only replaced No. 1 overall pick Caleb Williams, had ice in his veins and drove onto the field late in the game to help the 23rd-ranked Trojans to a 27-20 win over No. 13 LSU in Las Vegas on Sunday night.

With the score tied at 20 with 1:47 left and a timeout, it was all USC needed. Moss completed his first five passes of the drive and with 18 seconds left, Kyron Hudson made his second one-handed catch of the night to put the Trojans within range of a field goal.

CLICK HERE FOR MORE SPORTS COVERAGE ON FOXNEWS.COM

Running back Woody Marks (4) of the Southern California Trojans celebrates his touchdown against the LSU Tigers during the second quarter at Allegiant Stadium. (Stephen R. Sylvanie – USA TODAY Sports)

After the reception, LSU’s Jardin Gilbert was penalized for targeting, putting the Trojans at LSU’s 13. Woody Marks then ran in for his second score of the night, giving USC a 27-20 lead over LSU with eight seconds left. Garrett Nussmeier’s initial pass for a miracle drive was intercepted, nearly giving USC the win.

The aforementioned Hudson had made perhaps the catch of the year earlier in the game, in the second quarter, and two plays later the Trojans reached the end zone on a score from Marks, making the lead 7-0.

Running back Woody Marks (4) of the Southern California Trojans celebrates his touchdown against the LSU Tigers during the second quarter at Allegiant Stadium. (Stephen R. Sylvanie – USA TODAY Sports)

LSU PLAYER CALLED FOR UNSPORTSMANIAL CONDUCT AFTER PRETENDING TO SHOOT A GUN AFTER A TOUCHDOWN

LSU scored on a touchdown by Kyren Lacy on the ensuing drive. After the score, however, he appeared to fake firing a gun, resulting in a 15-yard penalty on the kickoff. USC took advantage of this, but ultimately had to settle for a field goal. LSU matched it, and USC missed a field goal near the end of the half to go into the locker room tied at 10-10.

Both teams traded punts to start the second half, but USC found the middle of the uprights midway through the third. LSU responded, however, with a seven-play, 73-yard touchdown drive that ended in Nussmeier’s second touchdown, this time from Aaron Anderson.

Midway through the fourth period, USC found itself at LSU’s 36-yard line and elected to attempt it on 4th-and-9, but Moss’ pass was incomplete. But after forcing a three-and-out, the Trojans needed just three plays to take the lead, when Moss found Ja’Kobi Lane for an impressive over-the-shoulder touchdown grab to put USC up 20-17 with 5:44 remaining. LSU, however, hit a tying field goal on its ensuing drive. But it clearly wasn’t enough.

Moss completed 27 of his 36 passes for a personal-best 378 yards, while Marks ran for 68 yards on his 16 carries, two of which resulted in touchdowns.

Southern California Trojans quarterback Miller Moss (7) throws a pass against the LSU Tigers during the first quarter at Allegiant Stadium. (Stephen R. Sylvanie – USA TODAY Sports)

CLICK HERE TO GET THE FOX NEWS APP

Nussmeier replaced reigning Heisman Trophy winner Jayden Daniels, who immediately pursued Williams in the NFL Draft. He impressed by completing 29 of 38 passes for 304 yards through the air. Lacy was the leading receiver with seven receptions for 94 yards.

USC is expected to climb significantly in the rankings and they go home to host Utah State on Saturday. It will be interesting to see where LSU finishes as they host Nicholls next weekend.

Follow Fox News Digital’s sports reporting on Xand subscribe to the Fox News Sports Huddle newsletter.