"Chiefs quarterback Matt Cassel's right hand injury, suffered late in Sunday's loss to Denver, is far more serious than initially thought and could end his season.

Haley said the injury is "significant" and will require surgery.

"That's a possibility," coach Todd Haley said Monday when asked if Cassel could be done for the year. "I wouldn't say it's an absolute."

Cassel hurt his throwing hand in the Chiefs' home game against the Broncos, a 17-10 loss that dropped them to 4-5.

For now, Cassel will not be placed on the injured-reserve list, which would officially end his season."