Brian Orakpo. (John McDonnell/The Washington Post)

The Washington Redskins will play without three defensive starters as they host the Pittsburgh Steelers tonight at FedEx Field.

Orakpo suffered a bruised right thigh in last Thursday’s practice, and remained sidelined on Friday. He went through a pregame warmup, but was held out of Monday night’s game as a precaution.

Meriweather, who is working his way back into form after a torn anterior cruciate ligament ended his 2012 season, practiced four consecutive days last week – his most extensive stretch of training camp. But the team elected to hold him out of a second consecutive preseason game. Meriweather played on the scout-team defense last week, recording two interceptions and a handful of pass breakups. He hopes to be recovered in time for the start of the season.

Wilson, who had surgery to repair a torn labrum this past offseason, practiced on the scout-team defense last week, but also has worked as the starting right cornerback. He was held out of Monday’s game as a precaution as well.

Rookie David Amerson will start in place of Wilson. DeJon Gomes started at strong safety during last week’s practices. And Rob Jackson and Darryl Tapp rotated as the first-team right outside linebacker when Orakpo got hurt.

Also ruled out for Monday’s game are quarterback Robert Griffin III (knee), wide receiver Donte Stallworth (hamstring), linebacker Roddrick Muckelroy (shoulder), linebacker Nick Barnett (knee) and tight end Emmanuel Ogbuehi (ankle).

Rookie running back Chris Thompson and rookie tight end Jordan Reed are expected to make their NFL debuts against the Steelers. Starting running back Alfred Morris, who didn’t play last week, also is expected to suit up for the first time this preseason.

Photos from Monday night:

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