SANTA CLARA, Calif. – Super Bowl 50 was a painful enough game to watch, so just imagine how painful it was to play in for the two superstar quarterbacks. The NFL hung a pair of massive posters hanging from Levi’s Stadium, one of the Carolina Panthers’ Cam Newton, just entering his prime, and the other of the Denver Broncos’ Peyton Manning, exiting in his twilight. It was the last time they looked that good all day.

Two superb defenses hijacked the plotline, ruined a beautiful story – and they made it ugly. Lady Gaga’s eye-spangled, chest-pounding rendition of the anthem, which had Newton laying back his head with eyes half shut in an expression of the sublime, was the only pretty moment of this thing.

“This game was like this season has been. It tested our toughness, our resilience and our unselfishness. It’s only fitting it turned out that way,” Manning said.

With five minutes left in the game, you were wondering whether the Broncos would be the first NFL team to ever win a Super Bowl without an offensive touchdown. The 39-year-old Manning had given up an interception, a fumble and been sacked five helmet-splitting, arm-stripping times. But his opposite, the thunderbolt-throwing 26-yard old colossus Newton, wasn’t much better. He too had given up a fumble and an interception.

Still, the table was all set for Newton – the most charismatic young face of the league. The Panthers trailed just 16-10, with plenty of time on the clock, and a TD drive would win it. Newton stood in the pocket, facing a third and 10 deep in his territory – and that’s when the Broncos’ Von Miller, the man drafted one spot behind Newton in 2011, got his right hand on Newton’s throwing arm and stripped him. The Broncos fell on the ball at the Carolina 4-yard line, setting up the Broncos’ only offensive touchdown of the game. It was a season-high fourth turnover for the league’s No. 1 scoring offense, and Newton would finish with seven sacks and completing just 18 of 41.

Somehow, the ugliness of the game matched the overall gritty atmosphere of this Super Bowl game. The NFL brought a gargantuan spectacle to a city struggling with rampant homelessness and facing a $100 million budget shortfall – a 2015 city government survey found there were 6,686 homeless, and many of them slept or panhandled on the streets around Super Bowl City, the blocks-long exhibition party at the Embarcadero.

Levi’s Stadium was a structure with the architectural charm of a half-built bridge, and bad turf that yielded divots even in pregame warmups. It sat in an expanse of Santa Clara surrounded by Silicon Valley corporate buildings a good hour from the city, with the Golden Gate Bridge nowhere in sight.

The Broncos’ and Panthers’ defenses commandeered the game right from the start, making it clear this would be a game about grit and not about golden boys. “Our defense has led the charge for all of us to be here,” Manning said last week, and that turned out to be an understatement that didn’t give the unit nearly enough credit.

The Broncos’ D was a unit built by the longtime veteran coach Wade Phillips, on pure, unthinking, fully committed aggression and speed. Phillips wanted to take advantage of the fleetness of young players like Miller, the 26-year-old linebacker who was born in 1989, the year Phillips made his first Super Bowl appearance with the Broncos.

According to linebacker Brandon Marshall, the unit traded nuance and went with simple schemes in order to play faster, emphasizing decisiveness over complexity. “Sometimes you think too much about what do I have to do,” Marshall said earlier in the week, “but with Wade it’s so black and white you don’t have to think as much, and when something happens, you see it and it’s bam, bam. You got to play fast. He doesn’t put a lot of restrictions on you, you don’t have to think what do I do here. If you can master it, you play fast, and simple.”

According to Marshall, the Broncos knew their defense was in for a big year in the preseason, when it dominated practices against the Broncos’ offense that was struggling with Manning. “We was handling them, we was killing ‘em,” Marshall says.

It was a unit that had huge ambitions, and that understood that it would have to carry the offense led by the fading Manning, whose arm produced just enough last few weak tosses to produce some field goals. The No.1 defense in the league believed they were capable of being the deciding factor – and also believed they were a historically dominant group. “You could see it was like an unmatchable deal,” Ware said. But Ware and his teammates also knew that nobody remembers great defenses – unless they win a Super Bowl.

“The only way a defense can become great is in the Super Bowl,” Ware said, “When you’re out there wreaking havoc.”

For more by Sally Jenkins, visit washingtonpost.com/jenkins.