Manchester United crashed to a humiliating 2-0 defeat at promoted Hull on Saturday in a dismal start to their Premier League campaign.
Michael Carrick's side were rocked by first-half goals from Semi Ajayi and Noble Mendy at the MKM Stadium.
Hull, who are back in the Premier League for the first time since 2017, were without 10 players due to injury but still put woeful United to the sword with a vibrant display.
Deep Dive
What were the key reasons behind Manchester United's defeat against Hull?
How did Hull perform in their first Premier League match after promotion?
What impact does this loss have on Manchester United's title challenge aspirations?
It was a chastening opening to the new season for United, who are expected to mount a title challenge after finishing third last term.
There was scant evidence that United are capable of going toe to toe with champions Arsenal on a dispiriting afternoon on Humberside.
Youri Tielemans and Andrey Santos were anonymous in their United debuts in midfield after joining from Aston Villa and Chelsea, respectively.
Carrick laughed off claims that United have been handed an easy start to the season, with their trip to Hull followed by a home game against Ipswich, another of the promoted teams.
The United manager's caution proved prescient.
{{/usCountry}}The United manager's caution proved prescient.
{{/usCountry}}Former England captain Alan Shearer summed up United's malaise with a damning verdict.
"Man United have been shocking, no hunger, they've been terrible," the BBC pundit said.
Carrick's steady demeanour during his interim spell after Ruben Amorim's turbulent reign played a major role in United's revival last season.
But, now installed as permanent boss, Carrick is expected to mount a challenge for United's first English title since 2013, adding a layer of pressure he did not have to endure last season.
Carrick has been asking for more signings, and United have agreed a deal for Brighton midfielder Carlos Baleba.
He will be demanding even more after this wretched performance.
Last season, Hull became the first team to finish sixth in the Championship and earn promotion via the play-offs since Blackpool in 2010.
Tigers boss Sergej Jakirovic had insisted this week that Hull could prove the doubters wrong after a host of pundits wrote them off as relegation certainties.
Toothless United
Even Jakirovic must have been pinching himself to make sure he wasn't dreaming during Hull's first win over United since 2017.
Initially, United were on top, and Luke Shaw's cross reached Bryan Mbeumo for a fierce strike that was repelled by Hull's debutant keeper Konstantinos Tzolakis.
United threatened again moments later when Noussair Mazraoui picked out Matheus Cunha for a low drive that Tzolakis saved at full stretch.
But Hull served notice they could trouble United as Ryan Giles' cross found Oli McBurnie for a header that forced a good stop from Senne Lammens.
United's defensive vulnerability at set-pieces was brutally exposed in the 17th minute.
McBurnie easily evaded sloppy marking at a Hull corner and drilled a strike that Lammens could only push out to Nigeria defender Ajayi, who gleefully poked home from close range.
Hull's first Premier League goal for nine years sparked wild celebrations all around the MKM Stadium as orange and black-clad fans danced in delight.
Patrick Dorgu squandered a golden opportunity to silence the Hull supporters, scuffing his shot wide from Harry Maguire's pass.
United were toothless in attack and in disarray at the back.
Hull pounced to double their lead in the 38th minute.
Regan Slater's pinpoint free-kick wasn't dealt with by United's shambolic defence, and Senegal defender Mendy thumped his header past Lammens.
Taunted by chants of "you're getting mauled by the Tigers", Carrick looked shell-shocked on the touchline.
Carrick sent on Marcus Rashford at half-time, but the England forward, who spent last season on loan at Barcelona, was unable to trigger a United revival.
Hull remained the more potent force, and Mohamed Belloumi fizzed a drive just wide from distance.
Tielemans and Santos were both hauled off midway through the second half, but it made no difference as United tamely surrendered.