It shouldn't have been nearly this dramatic.
That the Steelers went offside twice before Mike Badgley's eventual 29-yard field goal in the final seconds (and jumped offside during the winning kick, too) perfectly encapsulated this mess. And somehow, Antonio Brown's 154 yards weren't enough.
This stat is wild: The Steelers entered the game 174-0-1 in home games in which they held a 16-point lead at any point in the game, according to Elias Sports Bureau research.
"We had this game in our hands, and it fell a whole different way," linebacker Bud Dupree said.
This is how a you turn a 23-7 lead into a seven-point deficit in less than nine minutes of game time spanning the late third quarter to early fourth.
Safety Sean Davis accidentally rocks corner Joe Haden over the middle to turn an interception into a Keenan Allen touchdown off the bounce. Haden undercut the route and looked poised to get the pick before Davis dislodged the ball, which fell right into Allen's hands. "I had it. We collided. And I lost it," Haden said. "It's unfortunate."
The Steelers' offensive line commits a penalty and allows a Joey Bosa sack.
Desmond King returns a punt 73 yards for a touchdown with 12:52 left, with Steelers corner Brian Allen appearing to get blocked in the back during the return. Allen told reporters that even his daughter knew that was a block in the back.
Rivers throws to Keenan Allen for another two-point conversion.
A Steelers three-and-out.
Justin Jackson runs nearly untouched for an 18-yard score with 8:09 left against a defense that allowed 2 rushing yards in the first half.
The Heinz Field crowd goes silent.
The Steelers' offense mustered 35 yards over three drives to start the second half, allowing the Chargers to take a 30-23 lead.
"Can't play bad football against a good football team," said Ben Roethlisberger, who finished with 281 yards on 29-of-45 passing with two touchdowns and one interception.
The Steelers fought back with a 12-play, 78-yard drive. When rookie Jaylen Samuels finished it with a 10-yard touchdown catch over the middle, the Steelers set forth a plan to get the ball back with a three-and-out and notch another Big Ben comeback drive.
But the Steelers allowed the Chargers to take the clock all the way down with a poised, 11-play, 64-yard drive. Nose tackle Javon Hargrave nearly got a sack as Rivers delivered over the middle to Allen for a third-down conversion with less than two minutes left.
After allowing just those 2 rushing yards in the first half, the Steelers allowed the Chargers 83 in the second.
Los Angeles (9-3) certainly got some help. Rivers' 46-yard touchdown pass to Travis Benjamin in the first half shouldn't have happened because his right tackle had an egregious false start. Officials didn't call it.
But the Steelers (7-4-1) showed little resistance when the Chargers attacked, and Brown's season-high receiving yards total was buried by the loss. And think about this: Chris Boswell's missed extra point in the first half probably doesn't force Los Angeles to go for two twice, making Badgley's field goal for the tie instead of the win.
"You can't put any blame or point the finger," Brown said. "We got to point the thumb and figure out a way to win ball games without expecting flags."
In the first half, Roethlisberger was 6-of-7 for 117 yards on targets to Brown, compared to 9-of-18 for 55 yards and an interception to other targets. Once the Chargers made adjustments on Brown, Roethlisberger couldn't find the magic with other receivers. On the other side, Chargers coach Anthony Lynn said his team changed the scheme in the second half to keep Rivers cleaner and open rushing lanes.
Not even prime time, the Steelers' usual antidote to any worries, could help on this night. Now the Steelers' playoff future is murkier.
Defensive end Cam Heyward knows what all that means for the future.
"We have to get turnovers, we have to get sacks, we have to get more negative plays," he said.