In his eighth year with Roush Racing, a tenure that has included a Craftsman Truck Series championship and a Busch Series title, Biffle is considered a top contender for the Nextel Cup title.

Eleven races into the season, Biffle has three wins, four top-five finishes and seven top-10s.

"It just took a little while to iron out the details [of the contract] but I'm really happy to be making this announcement," Biffle said.

"I've had a long, successful career at Roush Racing with the Truck and Busch series' championships, and I'd love to bring Jack his third Nextel Cup championship."

Team owner Jack Roush shares Biffle's excitement about the driver's future at Roush Racing.

"Greg is a tremendous talent and his decision to remain at Roush is a commitment to his team," Roush said. "The No. 16 team has really come together and I think the best is yet to come for them. Greg and Doug [Richert, crew chief] have a chemistry right now that you don't find very often between a driver and a crew chief.

"It's taken a little while to get to this point but their on-track performance this season speaks for itself."