They’ve been heartbreakers plenty of times in the past, but maybe this time will be different for the Los Angeles Chargers.

The Chargers served notice of that possibility by improving to 9-3 with a 33-30 victory over the Pittsburgh Steelers on Sunday night. They remained a game behind the Kansas City Chiefs in the AFC West with one head-to-head meeting left, and maintained their lead in the AFC wild-card standings. Sure, they had help, from referees and from the Steelers themselves Sunday night, but a win is a win.

For instance, their kicker, Michael Badgley, got three chances at the game-winning field goal as time ran out. He missed his first attempt, but there was a flag on the play. His next attempt was blocked, but the Steelers were offside again. Although Pittsburgh was offside a third time on his final attempt, Badgley made that one and the penalty was obviously declined.

The Chargers, playing without running back Melvin Gordon (hamstring), started slowly, but Philip Rivers’s second half was impressive. He passed for 152 of his 299 yards and finished with 26 completions in 36 attempts. He was 13 of 16 in the second half, though, and Justin Jackson led the team in rushing with 63 yards and a touchdown on eight carries.

The game was downright ugly for the Steelers, who led 23-7 at halftime only to be outscored 26-7 in the second half. Despite two late touchdown drives by Ben Roethlisberger, the blown lead was Pittsburgh’s largest since 1981 and ended what the Elias Sports Bureau said was a franchise-record 174-0-1 run in protecting leads at home when up by at least 16 points.

For the Chargers, the victory was a sign that they’re playing with a bit of a chip on their shoulders. They’ve always been a nice team, one with talent that comes up short at the end, as Rivers remembers all too well.

“I saw ’em in my mind,” he said (via of the kinds of headlines he envisioned in the locker room at halftime. “ ‘Same ol’ Chargers . . . Can’t Win A Big Game . . . Not Ready For Prime Time.’ ”

Quarterbacks never forget, especially Rivers, who remembered a Sunday night game in which the then-San Diego Chargers rallied from certain embarrassment to beat the Denver Broncos 12 years ago.

“It was the same thing: Sunday night game, down big, nothing going right,” he said. “Then LT [LaDaininan Tomlinson] took that swing pass and went 51 yards. You remember!”

Rivers turns 37 on Saturday, and maybe this time things will work out differently for him and the team. The Chargers face the Cincinnati Bengals at home Sunday, then take on the Chiefs in Kansas City on Dec. 13 before finishing with a Dec. 22 home game against the Baltimore Ravens and a road game against the Broncos on Dec. 30.

In Sunday night’s game, there were a number of botched calls that could have flipped the result. Chargers right tackle Sam Tevi was clearly moving before the snap in the first quarter on Rivers’s 46-yard touchdown pass to Travis Benjamin. Steelers cornerback Brian Allen appeared to have been blocked in the back in the second half when Desmond King returned a punt 73 yards for a touchdown. And cornerback Joe Haden offered an emphatic “hell, no” when asked if he was offsides on Badgley’s missed field goal attempt at the end. No matter. It’s time to pay attention to the Chargers.

“These guys, they play four quarters,” Coach Anthony Lynn said. “We talked about playing with heart. We knew this was going to be a gut check for us. We believe in one another and play for each other and pull in one direction. We try not to listen to the outside noise.”

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