CLEVELAND — On crutches again, Montario Hardesty hobbled toward the stadium’s exit after his first NFL game for a doctor’s appointment.

He can’t outrun his knee problems.

Cleveland’s highly touted rookie running back, whose career at Tennessee was slowed by knee injuries, hurt his left one in the second quarter Thursday night in a 13-10 win over the Chicago Bears, a potentially major blow to the Browns’ offense.

“I hurt my knee making a cut,” a dejected Hardesty said. “I really don’t know what it is. I can’t say it’s not frustrating. I want to stay positive, get as much information as possible and return my focus to getting better. I’m hopeful whatever it is, I can get back as soon as possible.”

Hardesty said it felt nothing like any of his previous injuries. He’s scheduled for an MRI and more tests Friday.

Fellow Browns rookie Colt McCoy got his first pro start and went a perfect 13 of 13 for 131 yards in two-plus quarters. The former Texas star fumbled his first snap, but finally showed some potential in easily his best performance of an otherwise rough preseason.

Quarterback Todd Collins, recently signed by Chicago to back up Jay Cutler, completed 10 of 15 for 139 yards and a 15-yard TD pass to tight end Greg Olsen for the Bears (0-4).

Phil Dawson kicked a 36-yard field goal — set up when Browns defensive back DeAngelo Smith blocked a punt —— as time expired for the Browns (2-2).

Hardesty made his pro debut after missing training camp with a bone bruise, an injury he sustained in his surgically repaired right knee in a 1-on-1 tackling drill during the week before Cleveland’s veterans reported. He recently returned to practice and the Browns were excited about him finally getting on the field.

Hardesty showed his inside power before getting hurt, scoring on a 1-yard run in the first quarter. He finished with 25 yards on seven carries.

On a routine running play off the left side, Hardesty picked up 2 yards but stayed on the ground after being tackled. He grimaced as trainers worked on his leg before he walked slowly to the sideline, where Cleveland’s medical staff examined him.

Hardesty didn’t limp and was able to put full weight on his left leg as he left the field.

McCoy, who had his swollen left hand X-rayed after being stepped on, sympathized with his teammate.

“It’s too bad he left,” McCoy said. “He really ran hard on our touchdown drive. He was really looking good.”

The Browns traded into the second round to draft Hardesty, who gained 1,345 yards last season in the rugged SEC. Cleveland’s front office is high on Hardesty, believing he can step in as a starter or serve as a change-of-pace for Jerome Harrison, who at just 5-foot-9 and 205 pounds has durability questions.

Not wanting to risk injuries with their season openers looming, both teams rested most of their starters. Cutler didn’t play and the Browns sat starting QB Jake Delhomme and backup Seneca Wallace.

“Let’s hope nobody gets hurt,” Browns president Mike Holmgren, his right leg still in a cast from foot surgery, said before the game. He was driven around in his golf cart.

Unfortunately, the Browns may have lost their top running back.

Hardesty’s injury could keep James Davis on the roster. He gained 66 yards on 15 carries and caught five passes for 53 yards before leaving with a leg injury in the fourth period.

McCoy’s preseason has been shaky and it continued on his first play, a bad exchange on Cleveland’s first snap that the Bears recovered at Cleveland’s 19. Three plays later, Collins waited patiently for Olsen to get open behind Cleveland’s secondary.

“Really unacceptable,” McCoy said of his turnover.

He regrouped, though, and efficiently moved Cleveland’s second- and third-team offenses with short, precise throws. He twice completed 16-yarders but was sacked three times.

“This capped off my preseason,” McCoy said. “It felt great to get into a game, get into a rhythm and get a feel for the defense. Just being in the huddle, calling plays and leading drives — that’s football.”

Collins set up Cleveland’s TD with his own miscue. Backed up after a holding penalty, Collins was in the shotgun when he turned his head just as second-string center Josh Beekman hiked the ball. It bounced off Collins and Cleveland recovered at the 13.

“It was pretty comfortable on most things,” Collins said. “The formations and play-calling, some of them I wasn’t as sharp as I needed to be, but overall I thought it was a pretty decent effort other than the mishap we had on the shotgun snap.”

Bears coach Lovie Smith was pleased with Collins’ play.

“It was good to get him out there, especially with our No. 1 line,” Smith said. “That was the plan. I felt like he would handle the situation the way he did. He’s not a rookie coming in here.”

NOTES: Bears GM Jerry Angelo is comfortable with the 38-year-old Collins as Chicago’s second QB. “We’ve seen enough of him,” said Angelo, who plans to keep three quarterbacks. “His arm looks live. We feel good about him. We have confidence that he’s going to be our backup.” … Angelo said some of the final roster decisions will be difficult. “We have more decisions with the roster this year than we have had with past rosters on the fringe players.” … Dawson was wide on a 58-yarder on the final play of the first half. He also made a 24-yarder.