Arsenal's ill-discipline cost Mikel Arteta's men again as the nine-man Gunners were beaten 2-1 at Wolves on Tuesday to halt their charge towards the Premier League's top four.
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.
Arsenal have now been shown nine red cards since Arteta took charge in December 2019, three times more than any other Premier League club.
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.
Wolves' win at the Emirates in November was bittersweet as they lost talismanic striker Raul Jimenez to a fractured skull.
The Mexican has not played since and a lack of goals has seen Wolves plummet down the table.
Another bad night seemed in store for the hosts when Pepe fought his way through two challenges before firing into the far corner on 32 minutes.
Jose was brought in from Real Sociedad last month to ease the effect of the absence of Jimenez and made his first telling contribution for Wolves when Luiz was harshly adjudged to have tripped the Brazilian as he burst into the penalty area.
Neves coolly slotted the resulting penalty into the top corner with the final kick of the first half.
Moutinho then completed the comeback with his first goal at Molineux in three years at the club.
Leno's rush of blood to the head 18 minutes from time means he will miss the trip to Aston Villa on Saturday.
However, the damage to Arsenal's chances of Champions League football via the league already looks done as they remain in 10th, eight points adrift of fourth-placed Leicester, having played a game more.
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.
Sheffield United close to within a point of West Brom and 10 of survival with just their third league win of the season.