With quarterbacks EJ Manuel and Kevin Kolb sidelined by injuries, Buffalo Bills head coach Doug Marrone said undrafted rookie Jeff Tuel will start Week 1 under center against the New England Patriots.

Marrone also confirmed that starting cornerback Stephon Gilmore will miss the next 6-to-8 weeks with a fractured wrist that will require surgery, capping a trying week that has seen Manuel's preseason cut short due to a knee injury and Kolb's career called into question after sustaining another concussion.

Manuel, the 16th overall pick in April's draft, sustained a knee injury in Buffalo's second preseason game that required surgery, leaving his status uncertain for the season-opener.

Kolb took a knee to the back of his head on a scramble in the first quarter of Buffalo's loss to Washington and was suffering from concussion-like symptoms.

Marrone confirmed that Kolb suffered a concussion, but said that speculation on it being a threat to the seventh-year quarterback's career did not come from Kolb and that he is focused on recovery first.

The Bills brought in veteran signal-caller Matt Leinart on Sunday to address their quarterback issues, but Tuel, an undrafted rookie out of Washington State, will apparently be under center when the season starts on Sept. 8.

"I've been preparing to be the starter since the beginning. It can happen," Tuel said.

Gilmore, the 10th overall pick in the 2012 draft, sustained the wrist injury in the first half of Saturday's loss at Washington when he was making a tackle on Redskins wideout Aldrick Robinson.

Gilmore started all 16 games for the Bills last season, racking up 61 tackles, one interception and 16 passes defensed.