Consistency — and improvement — is what the Rams hope to get in exhibition against Chargers

The first-game performance against the Dallas Cowboys was brief, lasting only eight plays, and offered a few glimpses of development.

The next game against the Oakland Raiders was an extended opportunity, four series that resulted in three scoring drives.

On Saturday, Rams quarterback Jared Goff will have what is expected to be his final tuneup for the regular season when he faces the Chargers in a preseason game at the Coliseum.

Coach Sean McVay is looking for one thing from Goff, the No. 1 pick in the 2016 draft.

“You want to just see consistency,” McVay said.

Goff, 22, appeared to make great strides last week in a 24-21 victory at Oakland.

He played nearly the entire first half and connected with receivers, tight ends and running backs from the pocket and on rollouts. He completed 16 of 20 passes for 160 yards and a touchdown, but earned his highest praise from McVay for throwing away a pass rather than forcing the attempt and inviting a turnover or sack.

McVay wants more of the same from Goff against a Chargers team that held two joint practices with the Rams during training camp.

“If you can string together good decisions, throw the ball with great timing and rhythm and accuracy, that’s going to give yourself a chance to play the quarterback position at a high level,” McVay said.

Goff was not the only player on offense who performed well against the Raiders. Running back Todd Gurley ran with purpose and caught a pass. The offensive line opened holes and protected Goff.

Receivers also stepped up.

Robert Woods caught an early pass over the middle, rookies Cooper Kupp and Josh Reynolds caught touchdown passes and Sammy Watkins continued to work into the scheme.

Goff just missed connecting with Watkins on a pass in the end zone.

“The more reps you get with him, the more he can trust you and the more comfortable he is with throwing the ball to you,” Watkins said. “[It’s great] to have a guy that doesn’t even look your way, just look the safety off and throw you the ball, because he depends on you to be at the right spot.

“So that’s the page that I’m trying to build, and I think we’re moving in the right direction.”

McVay is encouraged by Watkins’ progress — and also by that of the entire offense.

“Last week was positive, but by no means does that mean we’ve arrived,” McVay said.

It is difficult to gauge where the Rams defense is at — and where it might be headed — because so many projected starters have not played during the preseason.

Star lineman Aaron Donald remains absent because of a contract dispute. Linebacker Mark Barron will not play against the Chargers or next week against the Green Bay Packers so that he will be sound for the Sept. 10 season opener, McVay said. Linebacker Robert Quinn and cornerback Kayvon Webster also have not taken a preseason snap.

The first-team defense, which has included a line consisting of tackle Michael Brockers and ends Ethan Westbrooks and Louis Trinca-Pasat, gave up two touchdowns against the Raiders. But cornerback Trumaine Johnson intercepted a pass to set up a Rams touchdown.

The last time the Rams and Chargers were on the field together — for the second of the two joint workouts — three fights broke out. Rams cornerbacks started all of them.

Johnson started the first when he took off his helmet and punched Chargers receiver Dontrelle Inman after they got tangled going for a ball in a one-on-one drill. Nickell Robey-Coleman then pushed Inman, inciting Chargers receiver Keenan Allen to body slam Robey-Coleman to the ground.

Johnson was among the Rams players who said they did not expect a reprise of the fights on Saturday.

“You’ve got to love competing,” he said. “What I hope is that it brings out the best in us, so we’ll see.”

gary.klein@latimes.com

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