GREEN BAY, Wis. -- The Green Bay Packers might be short-handed on offense heading into Sunday's game at San Francisco.

Tight end Andrew Quarless is expected to miss at least a month, if not six weeks, because of the knee injury he sustained in Monday night's win over the Kansas City Chiefs. Tests on Tuesday showed he sprained his MCL, according to a source, when he got hit on his left knee by Chiefs cornerback Marcus Peters in the second quarter.

"He has a knee sprain," McCarthy said Tuesday. "I don't think he will make it this week."

There's also concern that receiver Davante Adams will have to give his sprained left ankle a week or more to heal. Adams lasted just three plays against the Chiefs before he had to drop out, leaving his status up in the air. He initially was injured in the Week 2 win over the Seahawks.

It's the second significant knee injury for Quarless, who blew out his right knee on Dec. 4, 2011, against the New York Giants. He tore both the ACL and MCL and did not return until the 2013 season.

Quarless lost his starting job this season to second-year pro Richard Rodgers. Before Monday night's game, Quarless did not even have a pass thrown his way this season. He had two receptions for 14 against the Chiefs in what appeared to be a more expanded role.

The Packers have only three tight ends on the roster -- Rodgers, Quarless and rookie Kennard Backman. Backman, a sixth-round pick, has been inactive the first three games but likely will get his first chance to play on Sunday against the 49ers.