SEATTLE (Ticker) -- The Seattle Seahawks lost the first game in their new stadium Saturday night and may have lost their starting quarterback for up to a month as well.

ESPN is reporting that Trent Dilfer, who was promised the starting job by coach Mike Holmgren, has a torn MCL in his right knee and will be sidelined through the regular season opener September 8 at Oakland.

Dilfer, 30, sustained the injury, which has been officially listed by the team as a sprained knee, when he was hit by Indianapolis Colts defensive linemen Chad Bratzke and James Cannida after releasing a pass in the second quarter. Dilfer crumpled to the turf and clutched his knee before he was carted off the field.

Dilfer completed 9-of-11 passes for 94 yards and a touchdown before the injury.

Dilfer led the Baltimore Ravens to the Super Bowl title two years ago and signed with the Seahawks last season, but served primarily as a backup to Matt Hasselbeck.

In seven games, including four starts, Dilfer completed 73-of-122 passes for 1,014 yards with seven touchdowns and four interceptions. Seattle won all four games started by Dilfer and that was enough to convince Holmgren to re-sign him to a four-year, $18 million contract.

However, in Dilfer's absence, Hasselbeck will reclaim the starting job. He was 14-of-22 for 139 yards in Saturday's loss to the Colts.

Much-maligned for much of his career since being selected in the first round by Tampa Bay in 1995, Dilfer rejuvenated his career, winning his last 15 starts, including four with Seattle last season. He is 19-1 in last 20 starts, including postseason.

Dilfer, who spent his first five seasons in Tampa Bay before playing one season with the Ravens, has passed for 15,485 yards with 79 touchdowns and 89 interceptions during his career.