Even in the best-case scenario, it appears the Seattle Seahawks will be without Trent Dilfer for the regular-season opener and perhaps the first month of the campaign after the starting quarterback tore the medial collateral ligament in his right knee in a preseason game Saturday night.

	The news could have been worse for Seahawks starting quarterback Trent Dilfer.

League sources confirmed the MCL tear and, while such injuries typically do not require surgery, the normal rehabilitation period is between four and eight weeks. The sources also said initial indications were that Dilfer did not tear the anterior cruciate ligament, which would have sidelined him for the entire season.

Seahawks coach Mike Holmgren, who acknowledged Saturday night there was some ligament damage, confirmed Monday afternoon that Dilfer has an MCL injury and will be out four to eight weeks. The Seahawks are calling the injury a sprain, however, that appears to be just semantics. By definition a sprained ligament is almost always torn, and that is indeed the case with Dilfer's injury. Given the timetable for his recovery, an educated guess is that he sustained a second-degree sprain, a partial tear, of the ligament.

Dilfer was injured in the second quarter when hit by Indianapolis defensive linemen Chad Bratzke and James Cannida. He crumpled to the turf clutching his knee. Bratzke hit Dilfer high as he released the ball, and Cannida came in low. Dilfer had completed nine of 11 passes before being injured.

The eight-year veteran re-signed with Seattle in March, getting a four-year contract that could be worth as much as $18 million, and Holmgren named him the starter at the time. Dilfer, 30, has won his last 19 starts, including four in 2001.

In his absence, former starter Matt Hasselbeck will re-assume the No. 1 job. Holmgren said Saturday that if Dilfer is sidelined for an extended period the Seahawks might have to sign a veteran free agent. The options there are slim, and include names like Tony Banks, Dave Brown, Jeff George, Paul Justin and Scott Mitchell.

It is unlikely the Seahawks would attempt to bring back Ryan Leaf, who abruptly retired at the start of training camp last month.

Len Pasquarelli is a senior writer for ESPN.com.