The BYU Cougars offense took a big blow before facing Iowa State. Big 12 Player of the Year LJ Martin will be out for at least one month due to a lower-body injury, according to multiple reports. 

The news for BYU’s star running back also comes before the highly anticipated showdown with No. 3 Notre Dame. The 8th-ranked Cougars have boasted one of the most productive offenses in the conference this season. 

Martin carried the ball just twice for 16 yards in last week's 17-10 win over TCU before exiting the game. Martin was pulled down awkwardly and jogged off the field with a slight limp. He did not return.

With Martin out of the game, BYU was without their top two rushers. Sione Moa has been sidelined with an injury he suffered in Week 1. As a result, the Cougars rushing attack hasn't been nearly as effective. They finished with 154 yards and 4.1 yards per carry in wet conditions at TCU.

BYU QB Bear Bachmeier took over and added the game-winning score with a 21-yard run. Prior to the injury, Martin was a key piece in the BYU offense. He racked up 42 carries for 328 yards and three touchdowns in the first three games. 

In his career, Martin has racked up over 3,200 total yards and 29 total touchdowns. While Bachmeier is expected to step up for the Cougars, Martin will be hard to replace.

The timeline for Martin's return means he'll miss the Oct. 17 showdown against Notre Dame in Provo. The top 10 matchup will be critical for the College Football Playoff hopes of both teams. With Martin out, BYU goes back to the drawing board with a plan of what might work. The Cougars rank 16th nationally and fourth in the Big 12 with 235.5 rushing yards per game.

Martin has been a big part of that, but so has Bachmeier, who's one of the best pure athletes in college football. The issue for Bachmeier and the Cougars: what takes more of a priority? If the passing game can't take a hit, then abandoning the running game at full capacity could be an option. Otherwise, Bachmeier will be carrying the team on his shoulders in a few key matchups.

BYU will know what to do, especially against the Fighting Irish defense that plays well and it rarely makes mistakes. If the Cougars become one-dimensional, the next month will be tough without Martin. 

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