Chris Thompson’s ability isn’t in question; his durability remains so. (John McDonnell/The Washington Post)

While his teammates are preparing for Sunday’s regular-season opener at Houston, second-year running back Chris Thompson is trying to change an impression.

It’s an open-ended challenge, and it’s tricky to prove a negative. But for Thompson to get any playing time for Washington this season, the frequently sidelined back must convince Coach Jay Gruden that he won’t get injured again.

“I just have to go out at practice every single day and just come off the practice field healthy,” said Thompson, 23, asked how he plans to demonstrate his durability.

That may not be enough. Withstanding the rigors of weekday practice is hardly as impressive as emerging from games injury-free. And Thompson’s track record isn’t encouraging.

Drafted by Mike Shanahan in the fifth round of the 2013 draft, the diminutive back, listed at a generous 5 feet 8, missed his junior year at Florida State because of a broken back. His senior season was limited by a knee injury, and his rookie year in Washington was cut short by shoulder surgery.

He opened the 2014 preseason as the presumptive favorite for the Redskins’ third running back spot but missed two of four games because of a sprained ankle. In limited snaps, he finished the preseason with 12 carries for 23 yards, averaging 1.2 yards per carry. He also had six receptions for 53. Gruden opted to give the job to undrafted rookie Silas Redd, who led the team with 34 carries for 157 yards (4.6 yard average).

On Saturday, the NFL’s deadline for final roster cuts, Thompson was let go, along with third-year player Evan Royster and rookie Lache Seastrunk. But the next day, Thompson’s upside as an elusive, pass-catching back who could represent a change-up from the hard-charging Alfred Morris, earned him a spot on the 10-man practice squad.

“The cut day was kind of tough,” Thompson said this week. “After that, I started feeling better and tried to stay positive about the whole situation, trying not to stress too much. I just have to leave it in the coaches’ hands and try to improve every day in practice.”

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