Notre Dame will likely be without one of its top offensive weapons for the rest of the regular season.
Weis said he didn't know the exact nature of the injury but that it involved muscles in the shoulder. The team had originally feared Rudolph suffered a broken collarbone.
Weis said team doctors told him Rudolph could be available for the season-ending game at Stanford (No. 25 AP).
"I think that's a reach," Weis said. "I think he'll be able to practice again in December."
Rudolph has 33 catches for 364 yards and three touchdowns in nine games this season. He is one of the team's top red zone threats, and Notre Dame has struggled recently in that area. The offense came away with only two scores in six red zone trips against Navy.
The Irish (6-3) should get leading rusher Armando Allen back this week, Weis said. Allen has missed the last three games with an ankle injury but will start at Pittsburgh (No. 12 BCS, No. 8 AP) unless problems develop this week.
Brian Bennett covers Big East and Notre Dame football for ESPN.com