ORCHARD PARK, N.Y. (AP) — Josh Allen has the big arm. He has the size. And, now, he has the opportunity to take over as Buffalo's starting quarterback.

Bills coach Sean McDermott said Wednesday the rookie will make his first career start on Sunday against the Los Angeles Chargers.

Allen replaces second-year pro Nathan Peterman, who struggled badly in a 47-3 blowout loss to the Baltimore Ravens in Week 1. Peterman threw for 24 yards and two interceptions before being replaced by Allen in the second half.

McDermott declined to elaborate on his thought process behind the decision, instead saying it was "the right move" for his team more than 10 times.

"I don't feel the need, honestly, to elaborate," McDermott said. "We talk a lot in-house about decisions and things and what we've got to do and the right move at the right time, and right now, with all respect to your question, this is the right move for us."

The move is a jarring and significant change for Buffalo, which planned on bringing along the strong-armed, raw passer at a calculated and methodical rate before inserting him into the lineup. Chosen seventh overall this spring, Allen has ideal physical tools but has been considered a developmental prospect at the position.

The Bills, however, were forced into making a change following one of the worst losses in franchise history.

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