Maurice Hurt, right, along with Chris Horton, left, and Trent Williams cool off in ice tubs during training camp in 2012. (John McDonnell/The Washington Post)

Backup offensive lineman Maurice Hurt missed Thursday’s offseason practice to have arthroscopic surgery on one of his knees, Redskins coach Mike Shanahan said.

Hurt missed last week’s round of offseason practices with a groin injury. Shanahan wasn’t sure on Thursday which knee the third-year pro had injured. He is expected to be healed in time for the start of training camp, the coach said.

Hurt, a seventh-round guard/tackle out of Florida in 2011, appeared in 13 games last season, starting one of them at right tackle. He started eight games at left guard in 2011.

Also absent for Thursday’s practice was backup safety Jordan Pugh, who had an ear infection and wasn’t able to make the flight from Dallas, Shanahan said.

Defensive end Adam Carriker remains unable to take the field as he continues to rehab from a torn quad tendon. Carriker suffered the injury in Week 2 of last season and had to have surgery. He suffered a setback this offseason, and Shanahan said that there is no update on Carriker’s progress. The seventh-year pro, who restructured his contract this offseason, isn’t expected to return before the start of training camp.

Meanwhile, tight ends Fred Davis (Achilles’ tendon) and Jordan Reed (knee), running backs Chris Thompson (knee) and Roy Helu Jr. (toe), wide receiver Pierre Garcon (labrum), guard Josh LeRibeus (hamstring), linebacker Keenan Robinson (pectoral muscle), cornerbacks Josh Wilson (labrum) and Chase Minnifield (knee) and safeties Brandon Meriweather (knee) and Jordan Bernstine (knee) all continue to be held out of practice. Those players all went through conditioning and strength drills. And the tight ends, running backs and receivers caught passes from quarterback Robert Griffin III. Defensive lineman Ron Brace also did not practice.

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