The Tampa Bay Buccaneers have lost Earnest Graham for the rest of the season after the veteran running back tore his Achilles' tendon during Sunday's loss to the Chicago Bears, according to multiple reports. He's expected to undergo surgery soon.

Pro Football Talk was the first to report the extent of Graham's injury on Sunday, confirming Monday with a league source that surgery is required. Jason La Canfora of the NFL Network has also confirmed the news.

Graham started the last two games for Tampa Bay in place of LeGarrette Blount, who's sidelined with a possible MCL tear. In Week 6 against the Saints, Graham tallied 131 yards from scrimmage with 17 carries and two receptions, but on Sunday he recorded just three touches before going down. As you can see in this video, he fell to the ground untouched shortly after catching a pass out of the backfield.

The Bucs have a bye in Week 8, and it's possible that Blount may be ready to return in Week 9. That's good news, because Kregg Lumpkin, third on the depth chart when everybody is healthy, was extremely ineffective after replacing Graham against the Bears, tallying just 15 yards on eight carries.

For more on Tampa Bay's shrinking depth chart, visit SB Nation's Bucs blog Bucs Nation.