Jared Goff has two turnovers in Rams’ exhibition loss to the Chargers

Starting quarterbacks in the NFL rarely, if ever, play in final preseason games. The potential risk of injury — and the team’s fortunes — is too great.

So Jared Goff probably won’t get another start before the regular season opens in two weeks.

But after Saturday’s performance against the Chargers it certainly looks as though he could use one.

In three series, the Rams quarterback lost a fumble that was returned for a touchdown and also had a pass intercepted in a 21-19 defeat at the Coliseum.

“Obviously, a couple I’d like back,” Goff said. “It’s good to have this stuff kind of happen in the preseason and, hopefully, it can be avoided in the regular season.”

A week after he displayed encouraging signs against the Oakland Raiders in the Rams’ second preseason game, the Chargers converted Goff’s two turnovers into 14 points.

The Rams play their final preseason game Thursday at Green Bay, their last tuneup before the Sept. 10 opener against the Indianapolis Colts at the Coliseum.

Coach Sean McVay said the talk will be about the two turnovers, but Goff has done “a lot of good things” in the preseason.

“I think he’s improved a lot,” McVay said. “It’s going to be very important for us to maximize practice if that’s the direction we go where he doesn’t play against Green Bay next week.”

McVay’s attention is clearly pointed toward the opener: On Saturday, he kept running back Todd Gurley and nearly the entire starting defense on the sideline in street clothes so they would be physically sound for the Colts.

But Goff, the No. 1 pick in the 2016 draft, needed the reps as he continues to work toward proving that he can be a capable NFL starter.

McVay said this week that the offense’s performance against the Raiders was positive, “but by no means does that mean we’ve arrived.”

Goff, however, appeared to have made great strides.

After a short, turnover-free appearance against the Dallas Cowboys, Goff looked confident and sharp in the 24-21 victory at Oakland. He completed 16 of 20 passes for 160 yards and a touchdown and led scoring drives on three of the four series he played.

McVay said that the one thing he was looking for from Goff against the Chargers was consistency.

And early on, he appeared to have reason for optimism.

On the Rams’ second play, Goff dropped back, went through progressions and, on his third read, completed a pass to Robert Woods.

Two plays later, he showed good footwork in the pocket, eluded a sack and scrambled before tossing a short pass to running back Malcolm Brown for a big gain. At the eight-yard line, rather than risk an interception, he seemed to intentionally throw a pass over the head of a receiver in the end zone.

They were all plays that fulfilled McVay’s wish list for good decision-making by his quarterback.

But on the next play, Chargers defensive end Joey Bosa blew past right tackle Rob Havenstein and stripped the ball from Goff. The ball bounced on the turf before Chargers linebacker Melvin Ingram scooped it and ran 76 yards for a touchdown.

Goff seemed to have shaken off the play when he completed a pass to receiver Pharoh Cooper on the ensuing series.

Two plays later, he faked a handoff and looked toward the left side of the field, where Woods and receiver Sammy Watkins were finishing routes.

But Goff threw a wobbly pass that was short of both receivers. Cornerback Jason Verrett intercepted the pass, setting up another touchdown that put the Chargers ahead 21-0.

Goff said it was a “bad throw” and that he had felt a defender bearing down on him.

“I’ve got to stand in there and throw it,” he said.

Goff played one more series, handing off to running backs nine plays in a row before attempting a pass that fell incomplete. He connected with Woods on his final play, but it was short of a first down.

In three preseason games, he has completed 24 of 32 passes for 250 yards and a touchdown, with an interception and a fumble.

The uncertainty surrounding Goff matches the continuing mystery that is the Rams’ 3-4 defense.

Star defensive lineman Aaron Donald has given no indication that he plans to end his holdout over a contract dispute. Linebackers Robert Quinn and Mark Barron and cornerback Kayvon Webster all sat out again and will probably go into the opener without having played a preseason snap.

On Saturday, defensive tackle Michael Brockers, linebacker Connor Barwin and safety Maurice Alexander also were held out.

Chargers quarterback Philip Rivers faced a defense that included only two projected starters in cornerback Trumaine Johnson and safety Lamarcus Joyner.

Rivers connected with receiver Travis Benjamin on a 45-yard touchdown pass during the game’s first possession. Benjamin appeared to beat cornerback Blake Countess and Joyner on the play.

gary.klein@latimes.com

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