Cassel leaves after being sacked

Updated: August 30, 2009, 11:53 AM ET news services

KANSAS CITY, Mo. -- Chiefs quarterback Matt Cassel left the field favoring his left leg after being sacked on the third play of Kansas City's 14-10 preseason loss to the Seattle Seahawks on Saturday night.

Cassel was injured the first time he dropped back to pass, dragged down from behind by Brandon Mebane after the pocket collapsed. Cassel called timeout, then limped down the tunnel toward the locker room with a left leg injury and didn't return.

Signed to a a six-year, $63 million contract in the offseason, Cassel had a so-so first preseason game against Houston, then spent last week's game against Minnesota running for his life because of numerous offensive line breakdowns.

He was supposed to play into the third quarter against the Seahawks and show what he can do with more of the playbook available.

X-rays on Cassel's leg were negative, but it's not clear if he will even be available for next week's preseason finale against St. Louis.

The Chiefs haven't won any kind of game in nine months, a stretch that could continue to grow if Cassel is out for an extended period.

"We just have to get over that hump," said backup quarterback Tyler Thigpen, who may have hurt his chances of making the team by going 8-for-15 for 56 yards. "We had three close games that we could have won in the fourth quarter. That was a hump we couldn't get over last year and it kind of carried over."

Information from The Associated Press was used in this report.