Rampant United scored four times in the first half after Southampton’s teenage midfielder Alexandre Jankewitz was dismissed in the second minute at Old Trafford.
Ole Gunnar Solskjaer’s side hit five more after the break, tying them with Leicester’s 9-0 win at Southampton in 2019 and United’s own 9-0 victory against Ipswich in 1995.
Aaron Wan-Bissaka’s goal opened the floodgates and Marcus Rashford bagged United’s second.
Jan Bednarek’s own goal made it three for the hosts before Edinson Cavani added the fourth.
The goals kept coming as Anthony Martial and Scott McTominay netted before Bruno Fernandes’ penalty after Bednarek was sent off.
Martial and Daniel James scored in stoppage-time to complete an incredible display by United.
After the frustration of their shock defeat against Sheffield United and dour draw at Arsenal, the demolition job was a much-needed boost to their title bid.
United’s first victory in three league games means they are behind leaders Manchester City only on goal difference.
Pep Guardiola’s team have two games in hand, including one at Burnley this evening.
Jankewitz, making his first Premier League start, saw red after just 82 seconds for an ugly challenge that left stud marks on McTominay’s thigh.
United took advantage of their numerical superiority in the 18th minute when Luke Shaw swung a cross to far post and Wan-Bissaka bundled his shot past Alex McCarthy from close range.
Rashford doubled United’s lead seven minutes later with a composed finish from Mason Greenwood’s cross.
It was only Rashford’s second goal in his last 10 appearances in all competitions and his first in the league since December.
Rashford, subjected to vile abuse on social media recently, claimed the assist for United’s third in the 34th minute.
The England forward’s cross was turned into his own net by Bednarek’s out-stretched boot.
Cavani scored United fourth with a thumping header from Shaw’s cross in the 39th minute.
Martial ended his eight-game goal drought when he lashed home from close range in the 69th minute.
McTominay rifled home from 25 yards two minutes later and Fernandes struck from the spot in the 87th minute after Bednarek fouled Martial.
There was still time for Martial to score again before James capped the rout.
A seven-game unbeaten league run had propelled Arsenal back into contention for a return to the Champions League next season and they could have moved to within five points of the top four after Nicolas Pepe’s strike opened the scoring at Molineux.
But David Luiz’s third red card in two seasons as an Arsenal player for clipping Willian Jose on the stroke of half-time turned the game around.
Ruben Neves converted the resulting penalty before Joao Moutinho’s stunning long-range strike early in the second half put goal-shy Wolves in front.
Goalkeeper Bernd Leno then rounded off a miserable night for the visitors when he was also dismissed for handling outside his box.
A much-needed victory for Wolves ended an eight-game winless run and takes them 12 points clear of the relegation zone.
Nuno Espirito Santo’s men also completed a first league double over Arsenal in 42 years.
Arsenal remain in 10th, eight points adrift of fourth-placed Leicester, having played a game more.
“The team was really on top of the game, we should have been three or four-nil up and after the red card the game changed completely,” said Arsenal manager Mikel Arteta, whose team have had nine league red cards in his reign.
“I’ve seen it 10 times in different angles and I cannot tell you where the contact is,” he commented in regards to Luiz’s red card.
Sam Allardyce’s record of never being relegated as a Premier League manager is under severe threat after West Brom blew a lead to lose 2-1 at bottom-of-the-table Sheffield United.
Matt Phillips tapped home from close range to give the Baggies the lead shortly before half-time.
However, the Blades kept their slim chances of survival alive thanks to goals from Jayden Bogle and Billy Sharp.
Crystal Palace won 2-1 at struggling Newcastle.
Jonjo Shelvey’s fierce strike put Newcastle ahead after 71 seconds, but Palace equalised in the 21st minute through Jairo Riedewald’s rocket before Gary Cahill headed in four minutes later.