Chargers report: If Melvin Gordon can’t play, Austin Ekeler and crew will need to pick up the huge slack

The Chargers already played once this season without Melvin Gordon and that game turned out well for them.

They beat Tennessee in London 20-19 during Week 7.

But the prospect of losing their starting running back again, with a December push for a playoff spot looming, could be a bit more daunting.

Gordon suffered a knee injury in the third quarter of the Chargers’ 45-10 victory Sunday over Arizona. The severity remains uncertain, though Gordon hobbled off the field and did not return.

“I prepare every week like I’m going to be starting,” backup Austin Ekeler said. “If I’m getting more reps, then that’s what it is. I gotta pick up the slack for Melvin.”

Against Tennessee, Ekeler rushed 12 times for 42 yards and caught five passes for 26 yards. The Chargers finished that game with only 47 rushing yards on 16 attempts, both season lows. They averaged 2.9 yards per carry.

“We’re all going to have to pick up the load a little bit,” quarterback Philip Rivers said. “Thank goodness we have a guy like Ekeler that’s right there behind him, that we know we have a great deal of confidence in.”

After Ekeler, the Chargers have rookies Justin Jackson and Detrez Newsome. Jackson carried seven times for 57 yards Sunday.

Ekeler is a smaller, more slippery runner than Gordon. Undrafted a year ago, he has proven to be an effective complement to Gordon’s more classic style.

“Melvin and I are different running backs,” Ekeler said. “He’s a beast. I gotta step up my game … gotta keep carrying the load.”

The Chargers play at Pittsburgh next weekend, before returning to StubHub Center to host Cincinnati on Dec. 9. Defensive end Joey Bosa called the Steelers “our toughest challenge in a while.”

Catching on

Rivers’ 28 completions went to seven different receivers, including Sean Culkin, a second-year tight end who entered with zero catches in 11 career games.

Rivers hit Culkin for a 24-yard gain in the second quarter, setting up Gordon’s second touchdown that gave the Chargers a 21-10 lead.

“He was open,” coach Anthony Lynn said. “It just goes to show when you’re doing the right things, when you work your tail off like he does … he just took advantage of the opportunity.”

Two of Rivers’ three touchdown passes featured acrobatic, tip-toe grabs along the end-zone sideline, one by Mike Williams and the other by Keenan Allen. Combined, the two appeared to be about an inch in bounds.

Williams also caught Rivers’ first touchdown pass by going high in the air to pluck the ball away from Arizona defensive back Bene Benwikere.

“That’s what we expect from Mike,” Lynn said. “He’s a 50/50 guy. He can go up. He can jump out of the gym. He can go up and get the ball. That’s what he’s been doing all year.”

King returns

After Travis Benjamin took over the punt return duties for two games, Desmond King was back in that role Sunday.

He brought back two punts for 28 yards, including a 23-yard return during which he appeared close to breaking free.

King also had a 40-yard kickoff return to provide a spark.

“I had a couple good ones, one I could have possibly broken for a touchdown but I got tripped up,” he said. “I do feel like our special teams are starting to pick things back up. As long as we do our job, we’ll be good.”

Wild side

At 8-3, the Chargers lead the conference wild-card race by two games and trail Kansas City by a game in the AFC West.

They are trying to make the playoffs for the first time since 2013.

“We ain’t worried about where the franchise has been,” defensive end Melvin Ingram said. “We’re worried about right now. Right now, we’re in the race.

“We know what we’ve got in this locker room. It’s just all us in here together. The energy has been the same since training camp. We still know what we’re trying to do.”

Etc.

The Chargers’ 45 consecutive points were the most by the team since scoring 45 in a row on Dec. 14, 1969 in a 45-6 victory over Buffalo. … The Chargers also scored on five consecutive drives for the first time since Nov. 12, 2006 at Cincinnati. … Benjamin finished with three receptions for 47 yards. He hadn’t had a catch since Week 7.

jeff.miller@latimes.com

Twitter: @JeffMillerLAT