KANSAS CITY, Mo. -- The game clock at Arrowhead Stadium was running out on Jay Cutler and the Chicago Bears. With 7 minutes, 51 seconds to play in the fourth quarter, they trailed by 11 points and had not been able to dent the Kansas City Chiefs end zone.

But the Bears' Cutler-led offense began moving on the K.C. defense, converting third downs and chewing up yardage. In the span of 2:47 in the fourth quarter, the Bears quarterback threw two touchdown passes, including the game-winner to running back Matt Forte with 18 seconds to play, and Chicago walked away with an 18-17 victory over a struggling Chiefs on Sunday afternoon.

The outcome was minor compared to what was a greater loss for the Chiefs. Pro Bowl running back Jamaal Charles is believed to have suffered a torn ACL in his right knee early in the third quarter. If tests on Monday confirm that diagnosis, Charles is done for the season.

The Bears know about injuries; going into Sunday's game, they had 16 players on the league injury report. Cutler was playing with a rookie center making his first NFL appearance (draft choice Hroniss Grasu) and without the Bears top wide receivers, Alshon Jeffrey (hamstring) and Eddie Royal (ankle). But the often maligned Cutler threw the offense on his back and marched his club down the field.

He said the key was not allowing the young guys to think about what was happening.

"I tried not to huddle and kept them on the line and told them keep going, keep going," said Cutler, who threw for 257 yards, those two touchdown passes and no interceptions. "It was go, go, go, just to keep them in the moment so they wouldn't stop and think."

Down 17-6, the Bears took over at their 12-yard line and began an 11-play, 88-yard drive that ended with a pretty 22-yard touchdown pass to wide receiver Marquess Wilson. Cutler completed four of seven passes in the possession and added 12 rushing yards when he was chased out of the pocket.

The Bears defense forced a three-and-out by the Chiefs, and Chicago took over at its 33-yard line with 2:04 to play in the game. Eight plays and 106 seconds later, Cutler connected with Forte for a 7-yard touchdown throw that sealed the comeback.

"I knew we had a shot," Cutler said of the play. "We were just waiting to see if the guy (Chiefs safety Husain Abdullah) bit, so Matt could get around him, and he did. I knew where I was going with the ball."

The first half was ugly for the Bears as the Chiefs scored touchdowns on offense and defense, along with a field goal. The Chiefs reached the end zone the first time on the work of the defense as linemen Jay Howard and Allen Bailey overwhelmed the interior of the Chicago offensive line, sacking Cutler 2 yards deep in the end zone. Bailey knocked the ball out of the quarterback's hands, and Chiefs linebacker Ramik Wilson fell on the fumble in the end zone for a Chiefs touchdown.

Late in the first quarter, the Bears got on the scoreboard with a 44-yard field goal from Robbie Gould that made it 7-3.

Kansas City added an offensive touchdown on a 19-yard pass play from quarterback Alex Smith to wide receiver De'Anthony Thomas to cap a seven-play, 54-yard drive. Cairo Santos added a 35-yard field goal to set the score at 17-3 at intermission.

The Chiefs had the first possession of the second half and drove down the field, largely on the legs of Charles. But that's when disaster struck on a first-and-goal run from the Chicago 9-yard line. Charles was stopped for no gain by outside linebacker Sam Acho, and on the play Charles suffered the right knee injury that appears to have ended his season.

"A guy like that and what he means to this team and the type of player he is," said wide receiver Jeremy Maclin. "It's all very unfortunate."

Losing Charles seemed to take the wind out of the Chiefs, as they were unable to reach the end zone on that drive and a 27-yard field goal try by Santos was blocked by Chicago linebacker Pernell McPhee. The Bears went down the field and eventually picked up a Gould field goal of 30 yards and the score was 17-6 at the end of the third quarter.

All was quiet until midway through the fourth quarter, when Cutler started pulling and pushing the Bears offense down the field to a victory. Just eight days ago, the Bears were sitting winless after three games.

"It's huge," Cutler said. "To go 0-3 and then win two that we won in the fourth quarter, it shows a lot about our team and gives us some confidence. If we lose the Oakland game or lose this one, you can't build on that. To get ourselves back with two wins is big for us."

NOTES: Sunday was just the second home game in five weeks for the Chiefs. ... Bears K Robbie Gould became the leading scorer in franchise history for Chicago, picking up six points against the Chiefs, giving him 1,118 points and passing K Kevin Butler at 1,116 points. Gould grabbed the record with a 30-yard field goal late in the third quarter.