The pessimist will say that the Chiefs hardly looked like Super Bowl contenders. Their defense allowed Justin Herbert to throw for more than 300 yards and three touchdowns. Their offense struggled to consistently move the ball. And both sides had a lot to do with 10 penalties that impaired their ability to do much of anything.

The optimistic will say they still had a chance to pull out a victory.

“We can learn from this as we move forward. I’ve got to make sure I get my team in a better state there coming out, playing with more emotion. We were a little flat that first half, and that cost us,” Chiefs coach Andy Reid said after the 27-21 loss Friday night.

“There were some good things in there, but, again, we’ve got to make sure we take care of business.”

There isn’t a whole lot of time. The Chiefs have a Super Bowl rematch with the Philadelphia Eagles up next.

The matchup with the Chargers in Sao Paulo went awry right from the start, when wide receiver Xavier Worthy hurt his shoulder in a collision with teammate Travis Kelce. The Chiefs already were playing without Rashee Rice, who is suspended for the first six games of the season, leaving them without two of their best playmakers in the passing game.

No wonder it took Patrick Mahomes until the second half to get going.

By then, the Chiefs were playing from behind.

“I think it’s a learning moment, especially for the young guys on the team,” Mahomes said. “We’re going to get everybody’s best and we have to play up to that standard if we want to win football games. I feel we didn’t play to that standard.”

To be sure: The Chiefs have high standards. They have won nine consecutive AFC West titles, though they are suddenly 0-1 in the division. They have made seven consecutive AFC title games. They have played in the past three Super Bowls.

They also haven’t started 0-2 in a season since 2014 — Reid’s second season and the most recent time they failed to make the playoffs.

“You’re looking at the first game of the season, and you can’t judge the team’s success by one game or even one particular play,” Chiefs defensive tackle Chris Jones said.

“We have 16 more opportunities to get better. We’re going to watch, make some corrections, fix some errors. I think it was self-inflicted errors — offside, roughing the passers, multiple times we shot ourselves in the foot. Some self-inflicted wounds that we can fix, detail that up and I think we can improve in that aspect.”

What’s working

One of the big questions facing the Kansas City defense was whether it could stop the run, especially against a team that excels on the ground. It wound up holding the Chargers to just 90 yards on 25 carries, or 3.6 yards per attempt.

What needs help

As good as the Chiefs were against the run, they were lousy against the pass. Herbert was 25 of 34 for 318 yards and three TDs, and he was rarely under pressure. And when he was flushed from the pocket, he was able to scramble for positive yardage.

Stock up

Chiefs wide receiver Marquise Brown had 10 catches for 99 yards, helping atone for an early third down drop while making up for Worthy’s absence. He was hurt on their first preseason play last season and didn’t return until late in the season, so the Chiefs have waited a long time to see “Hollywood” have a real impact on a game.

Stock down

Right tackle Jawaan Taylor was called for two holdings penalties and two false starts, costing the Chiefs offense 30 yards when it was struggling mightily to move the ball. He was the NFL’s second-most penalized player last season.

Injuries

The Chiefs hope to learn more about Worthy’s shoulder injury when he undergoes an MRI exam in Kansas City.

Key number

57 — Mahomes led the Chiefs in rushing with more than half of their 98 yards on the ground.

Next steps

The Chiefs face the Eagles on Sept. 14 at Arrowhead Stadium.

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