With quarterback Robert Griffin III and the rest of the starters from the Washington Redskins looking on while being rested for the night, the spotlight shifted to the hopefuls on the fringes of the roster in Thursday’s preseason finale in Tampa Bay.

More than a victory, their goal was to make a play that earned them a place on the roster that first-year Coach Jay Gruden must pare from 75 to 53 by Saturday afternoon.

In the crowded competition at running back, three contenders with contrasting styles jumped out — elusive Chris Thompson, powerful Silas Redd and speedy Lache Seastrunk, who turned a short reception into an 80-yard blur of a touchdown.

It was exactly the combination of speed and power Gruden has wanted to see from the bunch all preseason, but it likely only muddled the decision-making in the wake of Washington’s 24-10 victory.

Redd, signed as an undrafted free agent from Southern California, carried a team-high 14 times for 79 yards, including a one-yard touchdown run that capped Washington’s scoring

Kicker Zach Hocker feels the weight after missing a fourth-quarter field goal that may have swung the advantage to Kai Forbath in the battle to be Redskins opening-day kicker. (Toni L. Sandys/The Washington Post)

“I’m going to be antsy — anxious to get a call saying I’ll be staying or not,” Redd said. “As far as my play if, God willing, I stay, I’ve got to get better on special teams.”

With backup quarterback Kirk Cousins joining the starters on the bench — a precaution against pointless injury — third-string quarterback Colt McCoy played the entire game for Washington and led four impressive scoring drives but threw two interceptions in the end zone.

McCoy moved the ball briskly, rolling up 321 yards passing in a 22-for-29 performance.

“I’m not sure if it mattered one way or the other on their decision,” said McCoy, who’s unlikely to vault ahead of Cousins on the depth chart. “But I’m excited and glad to play a whole game.”

In the battle for kicking honors, incumbent Kai Forbath took the upper foot, connecting from 45 yards. Rookie Zach Hocker missed a 39-yard attempt in the fourth quarter.

And injuries ended the night for two Redskins hopefuls. Nose tackle Chris Neild will undergo tests on what’s believed to be a torn anterior cruciate ligament, Gruden said.

And linebacker Akeem Jordan likely sprained a medial collateral ligament, a team official said, after his left leg was rolled up by a Tampa Bay defender.

Running back Silas Redd (14 carries, 79 yards, one touchdown) makes his best case for sticking around after final cuts Saturday. (Toni L. Sandys/The Washington Post)

With the victory, Washington concluded its preseason with a 3-1 record. But it’s a mark that obscures the very real struggles of the first-team offense, which failed to score a touchdown and committed three turnovers in its three outings, and of Griffin, who has looked tentative as a retooled pocket-passer despite being surrounded by a turbo-charged fleet of receivers.

Relegated to the bench for their own protection, Washington’s starters have 10 days to get in gear before their Sept. 7 regular-season opener in Houston.

Thursday’s preseason finale wasn’t about the stars, however. It was about the supporting cast and the competition for a limited number of roles.

With Washington getting in 66 offensive plays to Tampa Bay’s 49, Gruden will have plenty of footage to consult in making the most difficult cuts.

“I think guys had ample opportunities to show what they can do, and that’s what the preseason is all about,” Gruden said. “Now we have to make tough choices.”

The game got off to a ragged start, with neither team crossing midfield through the first four series.

With the Redskins facing a third and 12 on their opening series, Thompson entered the lineup and made a catch but was tackled immediately, six yards shy of the first down.

The Bucs’ third-string quarterback, Mike Kafka, took over in the second series and was quickly humbled.

Redskins defensive end Clifton Geathers sacked him for a nine-yard loss on his first throw; his linemate Frank Kearse sacked him later.

All told, it was an impressive showing by Washington’s defense, which held Tampa Bay (1-3) scoreless through the first half.

Working at right tackle, rookie Morgan Moses let a defender blow past with little argument on one play. McCoy, under pressure, still managed a seven-yard completion that put the Redskins in field goal range.

And Forbath hit from 45 yards to give Washington an early lead.

Outside linebacker Gabe Miller made the first big play for Washington, stripping the ball from Kafka and recovering it at the Tampa Bay 2-yard line as the first quarter expired. Two plays later, rookie wide receiver Ryan Grant made a leaping catch in the right side of the end zone to extend Washington’s lead to 10-0.

Thompson improved the more carries he got (eight, for 18 yards). The 2013 fifth-round draft pick needed a strong showing to convince coaches he’s worth a spot, given his history of injury.

Listed at a generous 5 feet 8, Thompson missed the previous two preseason games with a sprained ankle, was limited by a torn shoulder muscle his rookie season and missed his junior year of college with a broken back.

The Bucs didn’t get into the red zone until the third quarter — an achievement heralded by a cannon blast — and a field goal is all that resulted.

Seastrunk, who didn’t have a catch or a carry in the first half, hauled in the 80-yard touchdown reception in the third quarter that extended the Redskins’ lead to 17-3.