BYU running back LJ Martin, the 2025 Big 12 Offensive Player of the Year, is expected to miss four to six weeks with a lower-body injury, according to an ESPN report.

Martin suffered the injury in the first half of BYU’s 17-10 win over TCU on Saturday.

The timeline means Martin will miss the Cougars’ primetime showdown with No. 3 Notre Dame on Oct. 17. His status will also be in doubt for the BYU-Utah game on Nov. 7.

Martin rushed for 1,305 yards and 12 touchdowns last season. He has amassed 344 rushing yards this season.

Cougar running backs Preston Rex, Journee Tonga and Devaughn Eka will see an uptick in carries with Martin out.

All three have been productive in spots this season.

Rex has 18 carries for 94 yards and two touchdowns, Tonga has 19 carries for 157 yards and a score, and Eka has 12 carries for 87 yards and a touchdown.

“Very confident in those guys,” said quarterback Bear Bachmeier. “I think they are going to play great.”

It’s Tonga who might be the most intriguing. The freshman has impressed coaches not just with his limited snaps, but with his mind, too.

“He’s a young player who’s learned the whole offense,” offensive coordinator Aaron Roderick said. “Sometimes with a freshman you just pick a few plays and say, just know these plays. Journee can go in the game and play in any situation, and he knows what to do.”

He’ll likely be facing a lot more situations over the coming weeks. But BYU thinks he’s ready to handle them.

“I don’t want to make grandiose statements yet about him as a player, because he’s only played a little bit, but we really believe in him,” Roderick said. “He’s a good player. He’s a good back, and he’s a good receiver, and he blocks. He’s a good all-around player.”

And, as Bachmeier noted, he’s a pretty hard guy to take down.

“My first impression was, man, this guy’s got big calves,” Bachmeier said. “I actually played with his brother in youth football. So, yeah, I love the Tongas.”

Bachmeier could also see more reps in the running game with Martin out. The quarterback had 15 carries against the Horned Frogs after recording just 12 in BYU’s first three games.

The Cougars, though, would like to limit the hits he takes as much as possible, so expect the younger backs to get plenty of chances.

“Obviously we know how good LJ is, but we also know how good Journee, P. Rex and everybody in that room is,” BYU tight end Roger Saleapaga said. “This is college football. It’s always next man up, and I think we’re just excited to see some of the young guys have a chance to show what they can do.”