Published: Sep 03, 2012 10:51 PM EDT
Updated: Sep 04, 2012 6:32 AM EDT

AMES, Iowa (AP) - Iowa State running back Shontrelle Johnson was forced to confront the possibility that he'd never play football again.

Johnson has bounced back from months spent worrying about an ailing neck to be in the best shape of his life.

Johnson, who missed much of 2011 following a scary neck injury in early October, celebrated his return on Saturday with the best outing of his career. Johnson rushed for a personal-best 120 yards on 18 carries as Iowa State beat Tulsa 38-23.

Johnson and fellow junior James White will split carries on Saturday when the Cyclones (1-0) play at rival Iowa (1-0).

"It's a good feeling. I wasn't 100 percent sure if I'd be able to play again," Johnson said Saturday. "But I got the word from the (doctors) and it felt good to be back out with my boys."

Johnson was so quick and fluid against Tulsa that it made it easy to forget just how close he was to quitting the game.

Johnson opened 2011 as Iowa State's starter, and after a couple of slow games he broke out with 108 yards in a 44-41 triple OT win over the Hawkeyes.

But 10 carries into his game against Texas on Oct. 1, Johnson went for a block, got popped in the wrong spot and went down.

Johnson lost sensation in his hands and feet for about 10 seconds and was ruled out for the rest of that game. Johnson tried to make it back onto the field in subsequent weeks, but in late November he relented and had surgery on a bone joint in his neck.

Though the surgery went as planned, he needed months of therapy and rehabilitation before Johnson would even know if he'd be cleared to play.

After deliberating with his mother about his future, Johnson pledged to do all he could to rejoin the Cyclones. But he missed all of spring practice and most of Iowa State's summer activities before being cleared just before the start of fall camp in early August.

About all Johnson could do in his time away from the team was work out. So Johnson packed on a few extra pounds of muscle onto his 5-foot-9, 190-pound body.

"It was definitely a hard time for me, being around the program and football and not being able to take part in anything," Johnson said.

Iowa State strength and conditioning coach "Yancy (McKnight) did a great job with me working at speed and trying to get a little stronger, put on a few pounds, just focusing on things I could do in the weight room, and I think it makes a big difference on the field."

Johnson's successful return has helped make Iowa State's backfield as deep and as talented as it has been in recent memory.

White had a breakout season following Johnson's injury, earning honorable-mention All Big 12 honors in 2011, and 240-pound junior Jeff Woody excels in short-yardage situations.

White had 54 yards on 10 carries against Tulsa as the Cyclones coaching staff used the hot hand in Johnson, but the pair will likely share the load this season.

"There's two guys now, and Shontrelle is a special player," Iowa State quarterback Steele Jantz said. "We look forward to what he can do for us."

Johnson has always been one of the more outspoken and charismatic players on Iowa State's roster. Coach Paul Rhoads said that Johnson's attitude and on-field demeanor have remained intact despite all he's been through.

"I don't think there was ever any doubt in Shontrelle's mind that he was going to play. You're very thankful as an individual going through all that to get a second opportunity. There's no question he is," Iowa State coach Paul Rhoads said.

"When he put his helmet back on and started playing the game again, there was no change in Shontrelle Johnson's style of play."