

St. Louis Rams tight end Jared Cook (89) carries the ball into the end zone for a touchdown under pressure from Washington Redskins cornerback Bashaud Breeland (26) and strong safety Phillip Thomas. (Patrick Semansky/Associated Press)

Phillip Thomas will make his fourth straight start Sunday, and the game will essentially serve as the young safety’s final in-season audition for a key role in Washington’s defense next season.

Sidelined for all of his rookie season and a member of Washington’s practice squad for the first half of this year, Thomas has taken over as the starter at strong safety with Brandon Meriweather lost for the season because of a toe injury.

Thomas, a fourth-round pick in 2013, on Sunday recorded a career-high seven tackles, and in the eyes of his coaches displayed improvement in some areas. But Thomas still has room to improve, Coach Jay Gruden said.

“He did pretty good,” Gruden said. “He did some good things. … I thought Phillip, he tackled well and did a pretty good job. I’d like to see him get his hands on some balls, but otherwise, I think he filled in nicely.”

Thomas has made solid stops against the run and also made a strong open-field tackle on a pass play in the flat. Other times he has played with aggression while missing his keys in the run game, defensive coordinator Jim Haslett said. Thomas also has struggled with consistency in pass coverage.

“Each week it’s something new,” Haslett said when asked about the learning experiences Thomas encounters.

Thomas is the only safety under contract for the 2015 season with Brandon Meriweather, Ryan Clark, Trenton Robinson and Duke Ihenacho all on expiring deals.

The Redskins will make signings and possibly use draft picks to help upgrade the safety position, but Thomas must make significant strides to have a shot at winning the starting job.

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