Another Chargers comeback Saturday night is unlikely, and here’s why

They’ve trailed in three of their past four games, each of which ended in victory.

To be more precise, it was more extreme than that, the Chargers falling behind all three times by double digits.

Still, they came back to beat Arizona, Pittsburgh and Kansas City, mostly because they’ve outscored their opponents in the second half 74-30 over the past month.

“A lot of games are won in the fourth quarter in this league,” Pro Bowl center Mike Pouncey said. “But it would be nice to get up early and be able to finish a game not in the two-minute [offense] trying to come back and win.”

It would be nice, and on Saturday night at StubHub Center, it might be mandatory. In Baltimore, the Chargers are facing maybe the most comeback-proof team in the NFL.

Since Lamar Jackson took over at quarterback five games ago, the Ravens have become a run-first offense built to control the ball and empty the clock. They’ve won four times with Jackson as their starter, protecting leads by dominating possession in the second half.

Behind its top-ranked defense, Baltimore plays keep-away, averaging about 36 minutes of possession since Jackson took over. In the second halves of their past three victories, the Ravens limited each opponent to four possessions and 18 or fewer plays.

On Dec. 2, Atlanta had the opportunity to snap the ball only 13 times in the third and fourth quarters, one certain way to neutralize an offense that features Matt Ryan and Julio Jones.

“I feel good about it,” Baltimore coach John Harbaugh said of his team’s old-school approach of three yards and a cloud of cliches. “To me, it’s good football.”

With Philip Rivers, the Chargers have one of the most prolific and — this season, in particular — efficient quarterbacks in the game. But, if he’s stuck on the sideline, Rivers might as well be Ryan Leaf.

For an emotional player such as Rivers — who reacts in angry and animated ways when things go wrong on the field — imagine his reaction to being cooped up on the bench, the game’s outcome completely out of his control.

“We have to do a good job of making the most of our chances when we’re out there,” Pouncey said. “We can’t have too many three-and-outs because that’s what they thrive on.”

The Ravens won’t be the best team the Chargers face this season or even this month. But Baltimore might be the most flustering, combining that ball-hog offense with a defense that leads the league in fewest points and yards allowed.

“We just have to focus on the execution early and often, so we can get the lead and play from the lead,” Chargers coach Anthony Lynn said. “I like it when we play from the lead.

“If we do get behind, we always feel like we can come back, and I think that’s a good thing. But you don’t want to do that too often because, at some point, it’s going to bite you in the butt.”

The Chargers, tied with the Chiefs at 11-3, are playing for the top spot in the AFC. The fallback, should they finish second in their division, is quite a fall down.

If they aren’t the No. 1 seed, the Chargers will be the No. 5, as the conference’s top wild card. They could finish tied with the Chiefs for the AFC’s best record and still miss the top spot — Kansas City has the tiebreaking edge in division play — leaving their path to the Super Bowl buried under nothing but road games.

The Ravens (8-6) occupy the second wild-card slot but are guaranteed nothing beyond a lot of acid reflux over the season’s final two weeks.

“It’s going to be like a playoff atmosphere, like a playoff game really,” Chargers running back Melvin Gordon said. “We’re playing for something. They’re playing for something …losses are crucial on both ends.”

Gordon will return against the Ravens after missing three games because of a sprained right knee. Wide receiver Keenan Allen also is expected to play after suffering a hip injury last week.

That means the Chargers will have all their offensive starters back for a game in which a strong start could be critical. An early lead could force Jackson and the Ravens to throw the ball and, so far, the 21-year-old rookie has yet to top 14 completions or 178 yards in a game.

“The environment we’ve created here is a gritty one,” Chargers defensive lineman Damion Square said. “We have a lot of grit. We sign up for 60 [minutes] every game.”

The first 30 Saturday will be especially interesting.

Harbaugh back next year

Harbaugh will return to coach the Ravens next season, and the team says it’s working on an extension beyond 2019.

Harbaugh took over as Baltimore’s coach in 2008 and has taken the team to the playoffs six times, winning the Super Bowl in 2012.

The Ravens didn’t reach the postseason in each of the past three years, however, and are striving to end that streak with two games left in the regular season.

The Associated Press contributed to this report.

jeff.miller@latimes.com

Twitter: @JeffMillerLAT