Phillip Thomas Phillip Thomas will miss his entire rookie season with a Lisfranc tear in his left foot. (John McDonnell/The Washington Post)

The Washington Redskins officially placed rookie safety Phillip Thomas and second-year linebacker Keenan Robinson on injured reserve after each had season-ending surgeries during the preseason.

Thomas, the team’s fourth-round pick out of Fresno State, suffered a Lisfranc injury to his left foot in the preseason opener. Robinson, a fourth-round pick out of Texas in 2012, tore a right pectoral muscle early in training camp.

Meanwhile, the team waived cornerback Richard Crawford and linebacker Jeremy Kimbrough with injured designations. If Crawford, who on Saturday tore his left anterior cruciate, lateral collateral and posterior cruciate ligaments, and Kimbrough, who in the preseason opener tore the labrum in his right shoulder, both clear waivers, they will revert to Washington’s injured reserve list.

Crawford is expected to require a nine-month recovery following surgery, and Kimbrough said he expected a four- to five-month recovery once he has surgery.

The Redskins officially announced they have cut wide receiver Donte Stallworth as well as linebackers Ricky Elmore and Quan Sturdivant, fullback Eric Kettani, place kicker John Potter and wide receiver Chip Reeves.

The Redskins also have released backup tackle Jeremy Trueblood, and are believed to have cut linebacker Roddrick Muckelroy while pursuing an injury settlement with guard Jacolby Ashworth. But the team has yet to officially announce those moves.

Have a Redskins question? E-mail Mike Jones at with the subject line “Mailbag question” for him to answer it in The Mailbag.

What’s ahead:

● The roster must be cut down to 75 players from 90 no later than 4 p.m. on Tuesday.

More on the Redskins:

Royster expects to play in Redskins’ preseason finale | Meriweather, too

Moss willing to return punts if asked | Cousins says he’ll be back for Week 1

More cuts: Trueblood, Reeves, Sturdivant, Elmore and Potter

D.C. Sports Bog: Manley skips preseason football for sex | More Bog

Reid: Kerrigan’s increasing impact is no fluke

Mailbag: Emergency QB, the Lisfranc and Richard Seymour

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