Chargers players dressed and equipment managers tidied up the locker room after the team’s loss to the Kansas City Chiefs at SoFi Stadium. J.K. Dobbins sat motionless in his locker. The running back covered his head with a towel.

“I haven’t been in a place where I lost a lot, so I’m not used to it yet,” Dobbins said later. “And I won’t get used to it.”

The Chargers offense that emerged early as one of the most punishing running attacks in the NFL has faded into a two-game losing streak. Hampered by injuries and haunted by mistakes, the Chargers have scored just two touchdowns in their last 25 offensive drives entering Sunday’s game against the Denver Broncos.

“We gotta play cleaner football, that’s all, and we will,” offensive coordinator Greg Roman said. “You go through these little stretches sometime, and you just want to make them a little stretch, you don’t want to let that extend.”

Known for his wizardry in the run game, Roman had the offense humming behind 395 rushing yards in the first two games. He and coach Jim Harbaugh preached the importance of a balanced offense that could be quarterback Justin Herbert’s “best friend,” but the Chargers have averaged just 2.6 yards per rush in the last two games.

Injuries and self-inflicted wounds have hamstrung the offense, Roman said. The Chargers (2-2) haven’t shown everything they’ve worked on in practice because of in-game blunders, including seven offensive penalties against the Chiefs and two against the Pittsburgh Steelers.

Saddled with negative plays, the Chargers have faced third down with 10 or more yards to go 17 times in four games. Roman said he’s never been associated with an offense that has dealt with so many third-and-long situations.

The Chargers are 21st in the NFL in third-down conversions (36.4%) and just seven for 24 (29.2%) on third down in the two losses.

“We haven’t played the way we want to but there’s never a time to panic,” Herbert said. “Panicking doesn’t help. … We got the right guys out there. It’s a new offense. It’s a tough offense. We’re gonna get it picked up.”

With the running game’s struggles, Harbaugh is sensing the questions that will persist as the offense crawls along. The coach cut off a reporter Wednesday before he could finish asking whether the team would try to throw more with Herbert.

Chargers running back Gus Edwards (4) is upended and tackled by his face mask by Chiefs linebacker Nick Bolton (32) in the first half. Edwards is averaging 3.0 yards per carry.

(Gina Ferazzi / Los Angeles Times)

The former Pro Bowler has yet to pass for 180 yards in a game this season and is averaging 22.8 passes after throwing nearly 40 times a game in his first four seasons.

“If we throw it 500 times or 50 times, we just have to be executing as an offense,” Herbert said. “Selfishly, I’d love to throw the football, but I want to get this offense to be as best as we can. And what that looks like, it changes week to week.”

The passing plan started to reveal itself against Pittsburgh, Roman said. Herbert threw 16 times during the first half for 125 yards and one touchdown as the Chargers led 10-7. But an injury to left tackle Rashawn Slater left a gaping hole in pass protection and led to Herbert reinjuring his right ankle. The plan went out the window.

Although Herbert returned to start against the Chiefs, the lingering injury affected the game plan, Roman said. With the benefit of the off week, Herbert has returned to some team drills during practice for the first time since the initial injury, and Slater (pectoral) also returned in a limited fashion.

Right tackle Joe Alt was a full participant in practice Thursday for the first time since he injured a knee against the Steelers, potentially giving Herbert much-needed protection to jump-start the offense.

“I love it when Justin Herbert’s back there and is able to throw the football. We all do. It’s a thing of beauty,” Roman said. “But we’re trying to build something here that’s sustainable, that can win in a lot of different conditions under different circumstances. … But there are definitely going to be some days where we’re able to let Justin go to work, throwing the football. Those days are coming.”

Etc.

Linebacker Junior Colson (hamstring) was a full participant in practice for the first time since being injured against the Carolina Panthers. … Linebacker Joey Bosa (hip), running back Gus Edwards (ankle) and cornerback Ja’Sir Taylor (fibula) did not practice. … Defensive back Deane Leonard (hamstring) was limited.