SEATTLE – Just as they did last year, the Vikings kept most of their established starters out of their preseason opener, resting starters such as quarterback Kirk Cousins, wide receiver Justin Jefferson, edge rusher Danielle Hunter and safety Harrison Smith on Thursday night in Seattle.

The Vikings went into the game planning to hold their starters out, preferring to rest players before two days of joint practices against the Titans this week. They put the entire roster through pregame warmups, because of new NFL regulations that prevent teams from allowing separate workouts for starters not expected to play in preseason games. Once the team returned to the field for the game, however, nearly all of its veterans were set to watch the game from the sidelines.

Of the 11 players listed as offensive starters on the team's depth chart, Ed Ingram was the only one on the field at the beginning of the game. The right guard started at his normal spot, with second-teamers Vederian Lowe, Blake Brandel, Austin Schlottmann and Oli Udoh. Ingram played the first two series of the game before Alan Ali replaced him at right guard.

On defense, the Vikings had three starters — defensive tackle Khyiris Tonga, cornerback Akayleb Evans and safety Camryn Bynum — on the field to begin the game.

Mullens starts at QB before Hall comes in

Last year, Nick Mullens opened the preseason playing against the Vikings, completing seven of nine passes for 94 yards against them while playing for the Raiders. The Vikings traded for Mullens on Aug. 22 last year, and he began the preseason as their starting quarterback on Thursday night.

With Cousins sitting out, the Vikings made Mullens a captain on Thursday night and played him for the entire first half, where he completed 14 of his 20 passes for 139 yards and a touchdown, hitting Nick Muse for a 4-yard score when the tight end made a leaping grab in the back corner of the Seahawks' end zone.

After throwing incomplete on his first two attempts of the game, Mullens hit four of his six attempts on the second drive, also drawing a 15-yard penalty when Seattle's Derick Hall hit him late on an incomplete pass to Jordan Addison. The second drive ended with a Greg Joseph field goal to put the Vikings up 3-0.

The Vikings began the second half with rookie Jaren Hall at quarterback. The fifth-round pick completed two of his first three passes on his first drive, before throwing incomplete on a third down while he was flushed out of the pocket to his right.

While Mullens and Hall split playing time, Cousins spent much of the game wearing his helmet on the sideline, so he could listen to the play calls from coach Kevin O'Connell to the Vikings' quarterbacks.

Addison's debut: One catch, one impressive incompletion

First-round pick Addison, who's currently listed behind K.J. Osborn on the Vikings' depth chart, got the start at wide receiver, getting some early work as a run blocker before Mullens targeted him with the Vikings' first pass play. Though Mullens' first two throws to Addison were incompletions, the second one showcased one of the receiver's most impressive traits.

He stretched along the Vikings' sideline to catch a deep outside pass from Mullens, before officials called the pass incomplete and said the receiver didn't get both feet down. But replays showed Addison, who's made a number of slick sideline catches in training camp, had actually dragged both of his feet in bounds.

Addison's first recorded catch came on a deep over route from Mullens that went for 22 yards; the receiver worked back for a sliding catch on an underthrown pass after getting open in the middle of the Seahawks' secondary.

Busy first half for Chandler

Thursday night figured to be a busy night for running back Ty Chandler, as the Vikings try to determine whether the second-year man can overtake Kene Nwangwu for the No. 2 running back spot behind Alexander Mattison. Early in Thursday's game, the Vikings made good on their plan to get Chandler plenty of work.

He carried the ball five times in the Vikings' first two series, gaining 27 yards while catching two passes for 12 yards on those drives. With Jacob Sykes bearing down on Mullens, the quarterback hit Chandler for an 8-yard gain and a first down that moved the Vikings into the red zone for the first time.

Chandler finished the first half with 70 yards from scrimmage on 15 touches. "Ty Chandler's running the ball really well," O'Connell said in his halftime interview with the Vikings' television broadcast. "[It's] not always on really well-blocked plays, to be honest."

Thompson shines on special teams

Vikings undrafted free agent NaJee Thompson looked in training camp like he could win a roster spot because of his work on special teams. In the first preseason game, Thompson did his best to make his case.

He stuffed Seahawks' punt returner Easop Winston Jr. for no gain on a Ryan Wright punt in the second quarter. Then, as Wright punted toward the Seahawks' sideline at the end of the first half, Thompson raced across the field to down the ball as it checked up at the Seattle 2.