UPDATED 12/05/11 7:14 a.m.

CHICAGO (CBS) — The Bears were clobbered in an upset victory by the Kansas City Chiefs Sunday, and on top of it, they also lost Matt Forte to a sprained right knee.

The Bears (7-5) dropped their second straight after winning five in a row, but the biggest loss Sunday came in the first quarter.

Forte took a hit to the right knee from the Chiefs’ Derrick Johnson on a run for no gain deep in Bears territory with 6 minutes left in the period, another big blow for a team contending in the NFC.

Of course, quarterback Jay Cutler is already out indefinitely after breaking his right thumb against San Diego on Nov. 20, and now the Bears might have to make do without the league’s third-leading rusher.

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Forte Suffers Knee Injury

“It’s not a good feeling when you see your star tailback go down with a knee injury,” coach Lovie Smith said. “Part of the game. We’ll just keep our fingers crossed and hopefully it’s not that serious.”

In the fourth and final year of his rookie contract, Forte has been one of the Bears’ most valuable players. He has also been durable during his career, starting all 60 games since he entered the league in 2008, but that run could be in jeopardy.

Forte stayed on the ground while being examined by medical personnel and walked to the sideline under his own power after that hit to the knee. He remained there for several minutes before heading to the locker room.

Meanwhile, backup quarterback Caleb Hanie might be blowing his opportunity, although Smith says he shouldn’t be saddled with the blame for the loss.

“Don’t blame one guy for this loss,” Smith said. “We all had a big say in what happened today.”

Hanie did nothing to quiet the calls for the Bears to go after Donovan McNabb, completing 11 of 24 passes in his second start for Cutler. Besides getting sacked seven times against a team that came in with just 13, he threw three interceptions for the second straight week, and whatever chance the Bears had, basically disappeared when he got picked off in the end zone.

Hanie had completed four straight passes to put the ball on the Bears’ 13 after connecting on just one in the second half when Roy Williams juggled a throw. The ball hit off several defenders before a diving McGraw picked it off in the end zone with just over 4 minutes left.

“Obviously, the production wasn’t there,” Hanie said. “Three points is not good enough. I’ve just got to do a better job getting us in the right position and getting the ball to our guys.”

Yanked from the game earlier, the Chiefs’ Tyler Palko came back in and wound up completing 17 of 30 passes without an interception. He also threw for 157 yards and a touchdown.

It was a big improvement for a quarterback who got picked off three times in each of his first two starts after Matt Cassel suffered a season-ending hand injury.

Palko might get some more time, considering Chiefs quarterback Kyle Orton took just one snap at the start of the second quarter and left the game after injuring his right index finger.

“I really thought Tyler did a great job today,” Orton said. “He’s been through a lot. It’s great to see a guy get his chance and take advantage of it.”

As for Orton, Chiefs Coach Todd Haley said he doesn’t “really have much to give you” when asked about the injury.

Palko gave him enough, though. He connected with Dexter McCluster on a wild 38-yard pass to end the first half on a ball that got deflected by Brian Urlacher and Chris Conte, giving the Chiefs a 7-3 lead and their first touchdown in three games.

Kansas City (5-7) got a 21-yard field goal from Ryan Succop in the third quarter to make it a seven-point game, and Jon McGraw intercepted the struggling Hanie in the end zone in the fourth.

The Chiefs also recorded seven sacks — three by Justin Houston — and intercepted Hanie three times.

(TM and © Copyright 2011 CBS Radio Inc. and its relevant subsidiaries. CBS Radio and EYE Logo TM and Copyright 2011 CBS Broadcasting Inc. Used under license. All Rights Reserved. This material may not be published, broadcast, rewritten or redistributed. The Associated Press contributed to this report.)

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