New York Jets running back Stevan Ridley is unsure when he will be fit to return to the field ahead of the 2015 season.

The 26-year-old sustained a torn ACL and MCL during week six of the 2014 season when playing for the New England Patriots, and was ruled out for the campaign.

Ridley's contract with the Patriots expired at the end of the season and he signed for the Jets on a one-year deal, and although he has yet to practise for the club, the back has targeted being on the pitch for the start of next season.

"I really can't predict the future, man," Ridley told reporters. "I just know that, for me, I've got to be ready for week one. That's the goal right now.

"I'm not going to set myself up for any false hope or say that I'm going to do something that I'm not. What I will say is I'm working hard.

"I've just got to make sure that I'm 100% healthy, and that when I do hit the field, I'm making an impact."

Ridley has rushed for 2,817 yards and 22 touchdowns in his four-year NFL career.