Chargers start off strong but then quickly struggle in 36-7 loss to Saints

After sharing two joint practices and four preseason quarters, the Chargers and New Orleans Saints officially survived each other Saturday at StubHub Center.

And that was the best news to come out of a 36-7 Chargers loss that marked the end of the preseason for the regulars — at least the regulars who are healthy.

As it is, seven projected Week 1 starters didn’t play against the Saints, including running back Melvin Gordon, who missed the game because of a family matter.

The Chargers’ final exhibition is Thursday at San Francisco, an occasion that will be dominated by reserves and players who have little chance of making the final roster.

Despite the score, coach Anthony Lynn was pleased with how the Chargers ran the ball and stopped the run in the first half. He also noted that his team was called for only four penalties.

“I loved the way the first [defensive] unit went out and played,” Lynn said. “That’s one of the top rush teams in the league.… Offensively, we moved the ball on the ground. We know we can throw the football on anybody.”

New Orleans averaged 3.6 yards in 16 rushes in the first two quarters. The Chargers, principally Austin Ekeler and Detrez Newsome, averaged 5.4 yards in 13 tries.

Safety Derwin James, who was the most impressive rookie during training camp, started Saturday and started well. On the third play from scrimmage, he picked off Drew Brees.

James and Desmond King converged on Ted Ginn Jr., with James intercepting a ball that seemed to float on Brees.

“He just made a good play,” Lynn said. “We’ve been working him in the middle of the field. He showed his range … on that play.”

Another rookie, linebacker Kyzir White, also started as the Chargers continued to explore their options on defense.

After James’ interception ended the Saints’ first series, the Chargers forced New Orleans into a three-and-out, about as emphatic a start as is possible against an offense that last season led the NFL in yards per play.

In his only two series, quarterback Philip Rivers led the Chargers to a touchdown and to everything but a touchdown. He finished five for seven for 29 yards as the rushing of Ekeler and Newsome powered the offense.

The Chargers’ first possession lasted nine plays and covered 59 yards before dying on downs inside the New Orleans five-yard line when Rivers overthrew Mike Williams in the back of the end zone.

The next time they had the ball, the Chargers went 42 yards in eight plays with Newsome scoring from five yards out.

An undrafted rookie out of Western Carolina, Newsome appears to have a handle on the team’s third running back spot behind Gordon and Ekeler.

Those two possessions were it for Rivers, whose next appearance figures to come in the Sept. 9 opener here against Kansas City. He was replaced by Cardale Jones.

“I thought we did some good things — enough to be excited but not enough to relax,” Rivers said. “Either way, it went pretty good.”

In two preseason games — both of which ended for him after the first quarter — Rivers was 11 for 14 for 91 yards.

Jones struggled in his only quarter of play, before being lifted as a precaution. Lynn said Jones, who completed one of three pass attempts and was sacked once, has a slight groin strain.

Geno Smith started the second half and also had a difficult time. In the opening minute of the fourth quarter, he threw an interception that New Orleans cornerback Marcus Williams returned 58 yards for a touchdown.

Late in the third quarter, Smith had another interception taken back for a score. That play, however, was nullified by a pass-interference penalty.

Even though the game ended poorly, the Chargers could take solace in how it began.

“The way we ran the ball,” Rivers said, “if we can be balanced and run the football the way we did … we’ve got a chance to be a special offense.”

jeff.miller@latimes.com