LOS ANGELES — BYU won’t have a lot of healthy pass-catchers in its upcoming bowl game.

In the first half of Saturday’s game at USC, star tight end Isaac Rex sustained a serious ankle injury and had to be transported off the field on a cart, his ankle in an air cast.

Rex was trying to catch a throw from Jaren Hall with 5:50 left in the second quarter and tap his feet in the back of the end zone, but his ankle bent the wrong way.

The Cougars scored on the next play — a 5-yard touchdown run by Tyler Allgeier — to take a 21-10 lead, moments after Rex signaled to BYU fans in the corner of the end zone to thank them for their round of applause.

Rex, who had 12 touchdown catches last year, left the game without having a reception.

BYU receiver Gunner Romney dressed for the game but reportedly tweaked something in warmups and did not play.

The Cougars were already without receiver Neil Pau’u, who is from nearby Santa Ana, California, after he sustained an injury in the Idaho State game.

Pau’u made the trip but did not dress. He got off the BYU team bus outside the Coliseum and immediately used a knee scooter to get around.

Injury updates

BYU played again without former four-star recruit Chaz Ah You, who remains sidelined with an undisclosed injury.

The former Timpview High star hasn’t played since the Washington State game on Oct. 23. His status for the bowl game remains unclear.

Ammon Hannemann has been getting the bulk of the reps at the Cinco position that Ah You most recently played.

Matt Criddle got the start at safety Saturday, along with Malik Moore.

Backup right tackle Campbell Barrington, who replaced Harris LaChance in the starting lineup after LaChance sustained a lower leg injury in the 35-27 win over South Florida on Sept. 25, was available to play Saturday night, but Brayden Keim got the start at right tackle.

Barrington missed the 34-17 win over Georgia Southern last week after sustaining an injury during practice after the bye week.

USC played without its leading rusher, Keaontay Ingram, who was injured in the 62-33 loss to UCLA last week.

Ingram had rushed for 911 yards on 156 carries this season.

Also, former Corner Canyon starJaxson Dart made the start at quarterback for the Trojans, replacing the injured Kedon Slovis in the starting lineup for the second straight game.

Slovis was USC’s QB in 2019 when the Cougars upset the Trojans 30-27 in overtime in Provo.

Dart “has been trained by some really good coaches, (former BYU QB) John Beck being one of them,” BYU coach Kalani Sitake said.

Dart’s 6-yard touchdown run in the second quarter, after he dropped the snap, was USC’s first touchdown of the game.

Familiar faces

Former BYU football player Vic So’oto is USC defensive line coach and coached against his former team for the first time.

So’oto, who is from Southern California, played tight end, linebacker and defensive end for the Cougars from 2005-10 under coach Bronco Mendenhall.

So’oto made 45 tackles and five sacks his senior season in Provo.

Another former Cougar, C.J. Ah You, is a defensive quality control analyst for the Trojans. He’s the brother of BYU’s recruiting and player personnel director, Jasen Ah You.

C.J. Ah You played for BYU in 2001 and 2003.