Wolf Pack coach Chris Ault said Monday that Green, a second-team all-Western Athletic Conference pick at tackle last year, was injured two weeks ago.

The coach said Green would definitely miss Nevada's first two games, at Nebraska on Sept. 1 and at Northwestern on Sept. 8.

"We'll play that as we go. That was our starting center and our most experienced lineman," Ault said.

The 295-pound Green has played all three positions on the line, starting all 25 games of his career. The two players most likely to replace him are Kyle Robertson, who has played both center and guard, and junior Josh Catapano.

Preseason practice opened Monday for the Wolf Pack, who went 8-5 last season, including a 21-20 loss to Miami in the MPC Computers Bowl. They finished tied for third in the WAC last season and are picked to finish third again this year.