The Bills couldn't afford counting on McGee because starter Aaron Williams is expected to miss at least two weeks after hurting his right knee last weekend.
Pears, who started seven games this year, landed on IR a week after visiting a specialist to evaluate an injury that had not fully healed since he had offseason surgery. Gailey had warned last week that Pears could require a second operation.
Potter proved expendable because he was limited to handling kickoffs, a job that veteran Rian Lindell reclaimed the past two games. The Bills had used their second of two seventh-round draft picks to select Potter out of Western Michigan because of his strong leg and ability to kick the ball out of the end zone.
Potter's production had tailed off. Of 26 kickoffs, he managed 13 touchbacks, and only four in his final three games.
With two roster spots yet to fill, one option for Buffalo is activating tight end Mike Caussin, who had offseason surgery on his right knee. After opening this season on the Reserve/Physically Unable to Perform list, Caussin resumed practicing last week and is eligible to be activated within the next two weeks.
In another move, the Bills signed receiver Chris Hogan to their practice squad. Listed at 6-foot-1 and 220 pounds, Hogan split last season on the practice squads for the New York Giants and Miami Dolphins.
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