The Chargers lost several starters to injuries, including quarterback Justin Herbert, in a 20-10 loss to the Pittsburgh Steelers on Sunday at Acrisure Stadium. Herbert left the arena in a walking boot after re-injuring his right ankle on a sack in the third quarter.

Next up is AFC West rival Kansas City. Here's what we learned about the Chargers:

Taylor Heinicke is the next man

That's why Taylor Heinicke is here.

The Chargers traded a conditional sixth-round pick to the Atlanta Falcons for the 10-year veteran, knowing they needed to upgrade their backup quarterback in case Herbert got injured. The moment no one was waiting for came Sunday.

With only 24 days of experience in the organization, Heinicke entered the game in the third quarter and completed both of his pass attempts for 24 yards, but was sacked three times behind an offensive line that lost left tackle Rashawn Slater to a pectoral injury.

“I wish we would have given him a little more time for the surgery, but I was pleased with his performance,” head coach Jim Harbaugh said of Heinicke. “He's a competitor. Competitors are welcome here at the Los Angeles Chargers.”

Read more: Justin Herbert and the Chargers fail to win away against the Steelers

Acting reserve Easton Stick had a head start, having played in all three preseason games, but Heinicke caught up by spending three weeks immersed in the playbook. The system was so complicated that at first he even had trouble saying a play out loud.

He was inactive for the first two games to get his game in order. Then, late last week, when Herbert was limited in practice, Heinicke took over the majority of the training sessions, which helped him comfortably lead the offense despite the injury midway through the game.

Although Harbaugh immediately dismisses any “what ifs,” Heinicke has had to live in hypotheticals for a decade. The longtime backup has made it his mission to plan for just in case, and is ready to do so again while Herbert oversees the high ankle sprain.

“We will see how this week goes,” said Heinicke.

Don’t get carried away by the renovation

Since Mike Tomlin became head coach of the Steelers in 2007, the Chargers have had five permanent head coaches, one interim coach and two hometown coaches. Chargers offensive coordinator Greg Roman half-joked this week that the Steelers have had the same base defense since 1991.

This is culture.

And that's something the Chargers still strive for today.

Harbaugh has placed an emphasis on hard work and details while trying to change the narrative of a franchise that has seemingly spent years inventing creative but excruciating ways to lose.

Running back JK Dobbins said after the Week 1 win that the Chargers earned their confidence in close games through hard work in training camp: “We're not going to beat ourselves.”

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But on Sunday, the defense committed three penalties on an offensive run. The Steelers converted the 34 free yards into the decisive field goal. The missed tackles piled up while the Steelers ran for 100 of their 114 rushing yards in the second half.

“The difference is as big as the difference,” Harbaugh said. “I thought we were right there, back and forth. (The game) was where we expected it to be, and we ended up not getting it done.”

Change of the offensive line

It wasn't just Herbert's injury that set the offense back. Slater's injury may be almost as important, as the offensive line not only protects the franchise quarterback, but also plays a vital role in the running game that drives the Chargers' offense.

Slater, a second-team All-Pro tackle in 2021, was Pro Football Focus' second-best tackle after two games. He was off the bench at the end of the first half and left the field for good in the third quarter, shortly after allowing a strip-sack to Nick Herbig and pouncing on the ball to preserve possession for the Chargers.

On the next drive, Trey Pipkins III was lined up at left tackle and Jamaree Salyer at right guard. On the first play behind the newly formed line, Herbert took the sack that ultimately knocked him out of the game.

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“At the end of the day, we have to get better no matter what the circumstances,” Pipkins said. “We all know that wasn't our standard.”

Pipkins moved from right tackle to right guard this season with the signing of first-round draft pick Joe Alt. Although moving Pipkins to the outside resulted in two changes to the line rather than a one-for-one replacement of Salyer – who started 14 games at left tackle as a rookie in 2022 after Slater was injured – the Chargers made the decision because Pipkins was the team's “third-best tackle,” Harbaugh said.

Alt was also seen limping off the field towards the end of the game.

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This story originally appeared in the Los Angeles Times.