From the Chicago Tribune:

The Bears issued no official word on the severity of injuries to Thomas Jones, Ruben Brown and John Tait on Monday, but signs don't look as promising as hoped.

A MRI test on Jones' right knee revealed a stretched lateral collateral ligament. The results are being sent to noted surgeon James Andrews for a second opinion, but it's likely Jones will miss Sunday's game against Minnesota.

The Bears have had two productive skill position players on offense this year: Jones and Mushin Muhammad (who I'm really impressed with). For all the talk about defensive breakdowns from an otherwise top-notch defense, the Bears simply need Kyle Orton to play better, Cedric Benson to be an adequate replacement for Jones, and some receiver to step up as a deep threat.