With most of their starters reduced to spectators, the Washington Redskins completed an undefeated preseason Thursday night at Raymond James Stadium. Their 30-12 victory over the Tampa Bay Buccaneers was filled with subplots as Chris Thompson made a bid to be the Redskins’ punt returner, Evan Royster made a push for a roster spot at running back, safety Brandon Meriweather tried to show he’s ready for the regular season and quarterback Pat White attempted to continue his NFL comeback.

The signature moment for the Redskins in their final tuneup for the regular season came when Thompson broke free for a 69-yard touchdown on a first-quarter punt return, giving the coaches something significant to ponder as they pick the team’s roster and choose a returner.

But others made strong final impressions as well. Royster, the former All-Met from Westfield, ran for 59 yards and a touchdown on 11 carries. Fourth-stringer White played the entire game at quarterback. He threw an interception for a Buccaneers’ touchdown but ran for a touchdown of his own. He completed 13 of 22 passes for 181 yards and added 20 rushing yards.

“It’s not like we’re going out there not playing hard,” Royster said of the Redskins’ 4-0 preseason record. “And it’s not like our opponents weren’t playing hard. I think it just shows the depth we have on this team and what we’re capable of.”

Meriweather, after struggling at times during training camp and the preseason in his return from last season’s knee injury, played the entire first half at safety. He had a quiet performance but didn’t appear to suffer any setbacks.

Rookie cornerback David Amerson had an interception for the Redskins and place kicker Kai Forbath had three field goals. Redskins running back Keiland Williams and wide receiver Dezmon Briscoe left the game with what the team called in each case a sprained shoulder.

The Redskins withheld, by unofficial count, 22 starters and key reserves from the game. Coach Mike Shanahan stuck to his tradition of sitting down his starters in the preseason finale even though they’d played less than usual in the third exhibition game this summer. White got the start while the Redskins’ top three quarterbacks watched from the sideline.

“I’m just thankful to have this opportunity,” White said. “Who knows what’s going to happen. I don’t think I hurt myself. But I don’t know if I helped myself. Right now I’m just kind of, I guess, getting ready to come to work on Saturday.”

It’s unlikely that White has overtaken veteran third-stringer Rex Grossman to remain on the roster after the Redskins make their final cuts by Saturday’s league-wide deadline. But this night gave him a chance to audition not only for the Redskins, but also for quarterback-needy teams throughout the NFL as he attempts to return to the league after being out of the sport the previous three seasons. The former second-round draft choice from West Virginia played one season for the Miami Dolphins in 2009.

White got off to a good beginning when, on the game’s third play from scrimmage, he hung in the pocket under pressure and delivered a strike to Briscoe, who broke a tackle and raced to a 66-yard gain. A roughing-the-passer penalty added to the end of the play gave the Redskins a first down at the Tampa Bay 4-yard line. Royster needed two carries to get into the end zone from there, scoring on a one-yard touchdown.

Royster is vying with Williams and Thompson for one or two roster spots at running back behind starting tailback Alfred Morris and top backup Roy Helu Jr. Royster had a 36-yard dash on the Redskins’ third possession, which ended with a 37-yard field goal by Forbath.

“I just went out there and played my hardest,” Royster said. “That’s all I can do.”

The Post Sports Live crew discusses which Redskins players could be in danger of losing their position or could be cut in trimming down the roster to 53 players. (Post Sports Live/The Washington Post)

Thompson took center stage from there. The Buccaneers’ offense went three plays and out, and Thompson fielded Chas Henry’s punt at the Redskins 31. He waited patiently and then maneuvered around the first wave of three would-be tacklers without much blocking assistance. Thompson accelerated through the middle of the field, veered to his right around Henry and sprinted to the end zone for an eye-catching touchdown that perhaps will earn him a spot on the season-opening roster.

“The punter gave me a great opportunity,” Thompson said. “So I want to thank him first of all. . . . On that punt return, it all worked out. All the guys did a great job of blocking for me.”

The Redskins lost their punt returner, reserve cornerback Richard Crawford, to a season-ending knee injury suffered during Saturday’s win over the Buffalo Bills. Shanahan said during the week that there are other candidates, including veteran wide receiver Santana Moss. There are some questions about Thompson’s reliability after he fumbled twice on offense during the preseason. But he clearly has big-play capabilities.

White threw an interception that Buccaneers linebacker Najee Goode returned 37 yards for a touchdown early in the second quarter. But the Redskins responded with a 30-yard field goal by Forbath and a seven-yard touchdown run by White, on which he reached the goal line with a dive. That touchdown was set up by Amerson’s leaping interception of a pass by Buccaneers quarterback Mike Glennon and 35-yard return. Forbath added a 47-yard field goal in the third quarter.