Undrafted rookie Stephon Heyer is expected to draw the start at left tackle in this Saturday's preseason opener against the Tennessee Titans.

Heyer, 6-6 and 320 pounds, has impressed coaches through training camp and during the Redskins-Ravens scrimmage on Aug. 4.

"I think Heyer did a great job for us," Gibbs said. "He has continued to improve. I'd say he's going to be the starter. He had a good scrimmage. He played all of it."

Now Heyer could have the responsibility of protecting Jason Campbell's blind side versus the Titans. Chris Samuels, the Redskins' Pro Bowl left tackle, remains sidelined with a knee injury.

On the Redskins' depth chart released on Monday, Heyer is listed as the team's third-string lineman, behind Chris Samuels and fifth-year veteran Taylor Whitley.

Whitley also saw action at left tackle during Monday's practice, occasionally working against first-team defensive end Andre Carter.

Asked about Samuels's status, Gibbs replied: "I'm being told he's coming along well. Hopefully we're making good progress there."

Heyer originally signed with the Redskins shortly after the NFL Draft last April. At the University of Maryland, he started all 13 games at left tackle last year and was an honorable mention All-ACC performer.

-- WHITTICKER SUFFERS ANKLE INJURY

Guard Will Whitticker was carted off the field late during Monday's practice after suffering a high ankle sprain. He will undergo an MRI exam on Tuesday to further evaluate the extent of the injury.

Whitticker, listed at 6-5 and 356 pounds, left Redskins Park wearing a protective boot around his ankle.

He had been seeing a lot of playing time at right guard as Randy Thomas returns from arthroscopic knee surgery last June.

With Whitticker sidelined for the time being, the Redskins may have to reshuffle the line once second and third team players enter preseason games. Any number of versatile linemen could switch to right guard, including Ross Tucker, Jason Fabini or Mike Pucillo.

Fabini has been slowed by a groin injury and his status is day to day, Joe Gibbs said.

Asked about Fabini's status, Gibbs replied: "There's always a concern when a player is missing, but I don't think it's anything really serious. We'll see when he can get back."

-- INJURY UPDATE

Wide receiver Brandon Lloyd sat out Monday's practice due to a bout with shin splints. His status is day-to-day, Joe Gibbs said.

Fellow wide receiver Mike Espy was dressed in full gear for practice on Monday, but he did not participate in anything more than drills. Espy, nursing a bruised knee, is close to returning, though.

Ladell Betts will have a precautionary X-ray on his neck after absorbing a hard hit from Marcus Washington during Monday's practice. The injury is not considered serious.

Cornerback Jerametrius Butler has been slowed by a hamstring injury. He worked with head strength and conditioning coach John Hastings on some drills, but otherwise sat out practice.