FOXBOROUGH, Mass. -- New England Patriots wide receiver Julian Edelman underwent a precautionary standard knee procedure Thursday morning, a source told ESPN's Adam Schefter, and is expected to miss Sunday's road game against the Buffalo Bills.

The Patriots are practicing in the rain Thursday and Edelman is not on the field with his teammates. He practiced on a limited basis Wednesday.

Edelman, 34, has been limited all season because of his knee, and a source told ESPN he is expected to be sidelined for "some period of time." He leads the team with 21 receptions for 315 yards.

The Patriots also could be without receiver N'Keal Harry on Sunday, as he remains sidelined because of a concussion. That would leave the Patriots with just Damiere Byrd, Jakobi Meyers and Gunner Olszewski at receiver, likely leading to the team promoting someone from the practice squad.

Edelman leads the Patriots in receptions (21), targets (39), receiving yards (315) and yards per reception (15) this season.