A franchise for which so many seasons have gone sour, the Chargers’ fortunes on Sunday continued to sweeten.

They won their fourth in a row and fifth in six weeks in lopsided style, defeating the Rams 31-10 at SoFi Stadium.

The Chargers improved to 10-6 and clinched at least the AFC’s sixth seed. Entering the final weekend of the regular season, they still could move up to the No. 5 spot.

Sitting at 6-6 and with their fate teetering just four weeks ago, the Chargers have surged behind improved defense and improving health.

“We’re the team that you have to fear,” tight end Gerald Everett said. “You have to come out and play your best ball or you’re gonna lose. That’s something we really wanted to establish. I’m really happy that we’re actually on that path.”

Of the Chargers’ first eight victories, seven were decided by one score. Now they’ve won consecutive games by a combined 51-13 total. During this four-game win streak, their opponents have managed 44 points.

Against the Rams, they also righted an offense that had been sputtering, struggling to sustain drives and finish in the end zone. The 31 points marked the Chargers’ second-highest output of the season.

“The goal is to find your rhythm … in December and snowball that into the playoffs,” center Corey Linsley said. “I feel like we’re hitting our stride. Four-game win streak, it’s a huge, huge confidence builder.”

The Chargers also showed off a running attack that has been buried for most of the last four months. Austin Ekeler had a career-best 72-yard run on a day when he finished with 10 carries for 122 yards and two touchdowns.

They accumulated 192 yards on the ground in 31 attempts, an average of 6.2 yards per carry. The Chargers entered Sunday next-to-last in the NFL with a per game average of 84.9 rushing yards.

“It’s huge for our confidence moving forward,” Linsley said. “We had a lot of success running the ball. … I think it will pay off down the road showing that we can run the ball in multiple ways.”

The Chargers generated three red-zone trips and scored touchdowns all three times. They converted eight of 13 third downs. They amassed 431 total yards, their third-best effort of the season.

Late in the first half, leading 14-10 on Ekeler’s two rushing scores, the Chargers produced the game’s final 17 points to put away their Los Angeles rivals with no suspense.

“We know we haven’t played up to our capabilities,” Everett said. “We’ve missed throws. We’ve dropped throws. We’ve missed runs. We’ve missed blocks. Now, it’s reached a point where things are clicking at the right time.”

Everett continued his career year by scoring on a six-yard pass from Justin Herbert in the third quarter. Herbert later hit Donald Parham Jr. for a fourth-quarter touchdown.

Chargers wide receiver Mike Williams (81) makes a one-handed catch in front of Rams safety Nick Scott (33).

(Robert Gauthier / Los Angeles Times)

The highlights also included a spectacular one-handed catch by Mike Williams along the sideline for an 18-yard gain in the second quarter.

Williams needed all of his 6-foot-4 frame and the entire extent of his right-arm reach to snag Herbert’s pass, tapping both feet inbounds right in front of the Rams’ bench.

“I don’t know,” Williams said when asked to describe what he did. “Just make a play. Just react to the ball.”

Asked if he had seen a replay of the reception, Williams confirmed that he had. Then asked what the thought of the replay, he added, “It was crazy.”

After consecutive games without a touchdown pass — a career first — Herbert finished 21 of 28 for 212 yards and the two scores. He also wasn’t sacked after being sacked 25 times over the previous six games.

Williams had seven receptions for 94 yards as the Chargers scored as many as four touchdowns in a game for just the second time this season. Their five total scores Sunday came during a stretch of six possessions.

“I thought we played as hard as we’ve played on offense,” coach Brandon Staley said. “That was a big goal of ours today, just play harder than we’ve ever played. I thought you saw that in the run game. We finished drives with touchdowns.”

Defensively, the Chargers made it four impressive showings in a row as they welcomed back edge rusher Joey Bosa, who had been out since suffering a core-muscle injury in Week 3.

Bosa started and was credited with two tackles on an afternoon when his snap count was limited. Saying Bosa “improves our chances significantly,” Staley added the four-time Pro Bowl player took a clear step Sunday toward being fully back.

And the Chargers took another step toward becoming a potentially dangerous wild-card team. They will finish the regular season at 4-12 Denver looking to build even more momentum.

“This group was brought together for a reason,” Everett said. “This is the year to do it. …We have a real brotherhood forging here. I think it’s starting to show now and everyone can see it.”