SAN JOSE -- San Jose State coach Ron Caragher acknowledged for the first time Tuesday that running back Tyler Ervin may not return this season.

Ervin, who began the year as the starting running back, suffered a high ankle sprain on his second carry of the season-opener Aug. 29 against Sacramento State. Caragher said as recently as two weeks ago that he expected him to return this season, but that hope has started to fade.

"It's lingering on a little bit," Caragher said. "He's doing everything we've asked in the weight room. But I don't know if he'll coming back in the 2013 season."

Ervin, a junior, has not previously used a redshirt so he could return next season as a fourth-year junior and have two seasons of eligibility remaining. This week's game had unofficially been the target date to get Ervin back on the field but he's still not ready to return to practice.

If he played at all again this season, Ervin would not be able to redshirt.

"I've got to be smart about it if there's only a few games. He's doing all he can but he's not ready yet," Caragher said. "If he can't play at full speed, then we'll go that route. He's a special athlete and we'll welcome having him. I'm worried about this year obviously, but I'm sure a year from now we'll welcome having him back if the redshirt happened."

Ervin missed four games last season with a shoulder injury, making his return in the Military Bowl. He tied an SJSU record with two kick returns for touchdowns in a single-season last year and also shares the career record of three kick return scores.

When healthy, Ervin mostly spent last year as a change of pace speed back and receiving threat along with his kick return duties. He had 45 carries for 205 yards and a touchdown and 10 catches for 126 yards and a score.

Ervin was pegged as the starting running back in the spring, although durability was a concern for the 5-foot-10, 176-pounder. He missed most of spring with a hand injury and entered the season motivated to prove he could stay healthy.

"Since I was a kid, I might've been undersized but I always feel like I play like I was a lot bigger than I really am," he said in August. "So I always keep that chip on my shoulder, play as hard as I kind every down and do what's best for the offense."

  • With Ervin out for the foreseeable future and freshman Thomas Tucker still out with a concussion, the Spartans have turned to Brandon Monroe as a possible running back option.

    The true freshman from Del Oro High in Loomis played in the first two games at safety before spraining his ankle. He was cleared to play against Colorado State but didn't see the field.

    "We've got to have guys ready at all times," Caragher said. "Whether he gets ready by Saturday remains to be seen. But he is a good runner. We all knew that coming here. We all just felt that back in August and through recruiting that we needed more help at safety."

    Monroe was a star running back in high school, rushing for 3,456 yards and 42 touchdowns in three seasons. He was the Sacramento Bee's Player of the Year in 2012 and was the U.S. Player of the Game at the 2013 International Bowl in Austin, Texas. He rushed for 238 yards and three touchdowns in a 29-14 win over Canada.

    Monroe's first day at running back was Tuesday and so he's still learning the offensive playbook. But he did see time with the starting offense so there's a chance he gets some carries Saturday against Wyoming. Jarrod Lawson will start at running back.

    "Hopefully it'll add some good depth to the position," Caragher said. "He brings something to the position. He's a powerful runner, he's got good speed. He's got all those things you want in a running back. When you get to middle of the season, sometimes you've got to patch up holes."

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