NEW ORLEANS — Late Saturday night, Patrick Mahomes envisioned another close ending, another chance late in the fourth quarter, another moment that could deepen his legacy. He had already played in four Super Bowls at age 29, and he had come to expect a certain flow to them. He believed Super Bowl LIX and the Kansas City Chiefs’ historic pursuit at a third consecutive title would be decided late.

At their team hotel overlooking the Mississippi River, the Philadelphia Eagles were arriving at their own expectation. Their defensive linemen gathered in a conference room. Defensive line coach Clint Hurtt delivered a message.“All respect to the Chiefs, but I know who we are and what we’re about,” Hurtt told his players. “And there’s no reason for the game to ever be close.”

Sunday night inside the Superdome, Mahomes’s inevitability collided headlong with a ferocious, profoundly talented defense. His perception of the game — if not himself as a quarterback — would be utterly shaken. The Eagles clobbered the Chiefs, 40-22, and bullied Mahomes into a brand of turnover-streaked, almost helpless football that had been foreign to him.

In a game that could have delivered him an unprecedented achievement, Mahomes suffered the most comprehensive thrashing of his professional career. His offensive line provided him little chance at playing well, but his impatience and imprecision only exacerbated the Chiefs’ struggles. A quarterback of regal poise turned panicky and uncertain. Mahomes’s performance did nothing less than force him — three Super Bowl titles into his career — to take stock of the kind of quarterback he needs to be.

“I take ownership of this loss more than probably any loss in my entire career,” Mahomes said. “I put us in a bad spot.”

The worst margin of defeat of Mahomes’s career remained 24 points, from a 27-3 loss to the Tennessee Titans in Week 7 of 2021. But that owed only to a pair of cosmetic touchdown passes Mahomes threw in the final three minutes on Sunday. He had never been beaten so badly. The Eagles led 24-0 at halftime. They led 40-6 late in the fourth quarter. Mahomes had never been sacked more than five times in a game; the Eagles sacked him six times without needing to blitz. Mahomes threw two first-half interceptions, the first of which Cooper DeJean returned for a game-cracking touchdown midway through the second quarter. He lost a fumble in the fourth, a play even the quarterback who makes anything seem possible had no shot at recovering from.

Early in the week, Mahomes was asked if any game keeps him up at night. “That’s easy,” Mahomes said: The 31-9 Super Bowl loss the Chiefs suffered to Tom Brady and Tampa Bay Buccaneers four years ago, in which Mahomes could not survive a pass-rushing onslaught. That game now has company.

“Both suck,” Mahomes said. “There’s no way around it. Any time you lose a Super Bowl, it’s the worst feeling in the world. It will stick with you the rest of your career.”

In the final seconds of the game, teammates and coaches consoled Mahomes. He threw his arm around defensive coordinator Steve Spagnuolo, looking at the field with a 1,000-yard stare. He walked to midfield after the final kneel down, congratulated MVP Jalen Hurts with a handshake and navigated a mass of photographers. For nearly 11 minutes at a news conference, he answered questions with poise and grace, repeatedly crediting the Eagles and accepting full blame.

“The turnovers hurt, and I take all the blame for that,” Mahomes said. “Those early turnovers swing the momentum of the game. They scored a touchdown on one, and then they got a touchdown immediately after. That’s 14 points that I gave them.”

The Eagles bewildered Mahomes with a simple game plan. They used no “unscouted” tactics or scheme, Chiefs center Creed Humphrey said — everything they did Sunday night was what they had done before. Early in the two-week preparation, defensive coordinator Vic Fangio determined he would not adjust to his opponent or the magnitude of the Super Bowl.

“The way we play is the way we play our best,” Fangio said. “It’s just the style that fits our team the best. That’s how I wanted to start the game. When we started off so good, I just stayed with it.”

Fangio had hovered over Mahomes’s career well before Sunday night, indirectly dictating his evolution from gunslinger to surgeon. Fangio specialized in the shell-like defenses with two deep safeties that first stymied Mahomes when he seemed unstoppable early in his career, and that style of defense spread across the league and promoted a swell of short passing. As others copied Fangio, Mahomes adjusted by becoming a maestro of checkdowns and screen passes. The Fangio-Mahomes chess match had influenced the entire league and turned Mahomes, by this season, into a Brady-like distributor who could also conjure magic with scrambles.

Fangio stuck with his tenets Sunday night. He repeatedly told his players to “stop the second play” — keep Mahomes corralled in the pocket and don’t let him make magic on the run. He planned to blitz as little as possible, keeping seven defenders in constantly shifting coverage designs.

“Mahomes does very well against pressure, adding extra rushers,” Fangio said. “So I was hoping we could play him without having to do that.”

The Chiefs’ primary vulnerability all season, as they eked out dramatic victories, was their offensive line. Late in the year, they resorted to moving Joe Thuney from left guard to left tackle and inserting undrafted Mike Caliendo in Thuney’s spot. The Eagles’ defensive line kicked their teeth in.

From the Chiefs’ first drives, Mahomes was hesitant. The unrelenting pass rush harried him. The seven players in coverage forced him to throw through a dense forest of limbs. He could not conjure his usual improvisational flair, hemmed in by four pass rushers and unable to find uncovered receivers.

“In order to make a team blitz, you need to be able to beat what they’re showing,” Mahomes said.

The Eagles did not blitz once in the first half and still pressured Mahomes on 47 percent of his dropbacks. Fangio called only one blitz in the second half, when the outcome had already been decided.

Mahomes threw for 33 yards in the first half, the fewest in a championship game since Rex Grossman had 32 in the first half in Super Bowl XLI. His 10.7 quarterback rating in the first half was the third-worst of any quarterback in any game this season.

“He’s a human being, man,” Chiefs wideout DeAndre Hopkins said. “I guess the world got to see that.”

Mahomes’s first interception came when he tried to squeeze a pass into a nonexistent window to Hopkins. DeJean stepped in front of it and weaved into the end zone. Late in the first half, Josh Sweat — who also had 2.5 sacks — shoved Thuney into Mahomes as he released a pass. The ball fluttered into the diving hands of linebacker Zack Baun. Mahomes allowed that he had been bumped, but he would not accept a reprieve. “Got to find a way to make the throw,” Mahomes said.