Wolves picked up just their third point of the season in a 1-1 draw at Old Trafford, while Chelsea have won only once in seven league games after being held 2-2 by Bournemouth.
Arsenal avenged their only defeat in the last 25 games in all competitions earlier this month at Villa Park to take a firm grip of the title race.
Doubts over Villa’s ability to live with Arsenal and Manchester City over 38 games were realised as Unai Emery’s men were blown away in the second half at the Emirates.
After a tightly-contested first 45 minutes in which Villa had their chances through Ollie Watkins, Arsenal cut loose.
Mikel Arteta’s men could rely on a set-piece once more to break the deadlock when Gabriel Magalhaes outmuscled Emi Martinez to score on his return to the starting line-up from a hamstring injury.
Martin Odegaard’s fine through ball then teed up Martin Zubimendi to quickly double the Gunners’ lead.
Two quality strikes then rubbed salt in the visitors’ wounds as Leandro Trossard and Gabriel Jesus fired in from outside the box.
Watkins netted a consolation but third-placed Villa fall six points behind the leaders.
City can cut the gap at the top back to two points when they travel to Sunderland on January 1.
United wasted another chance at Old Trafford to boost their chances of a return to the Champions League next season.
Joshua Zirkzee’s deflected effort gave the Red Devils the lead, but Ladislav Krejci’s header snapped Wolves’ 12-game losing streak.
Ruben Amorim’s men remain in sixth, two points outside the top four.
Chelsea failed to lift the gloom at Stamford Bridge as Enzo Maresca’s decision to substitute Cole Palmer was booed by the frustrated home fans.
David Brooks gave the Cherries the perfect start but Bournemouth quickly showed why they have conceded more goals on the road than any other side in the English top flight.
Palmer equalised from the penalty spot before Enzo Fernandez was afforded acres of space to fire into the top corner.
But Chelsea failed to deal with a long throw for the second time in the opening 27 minutes when Justin Kluivert turned in Antoine Semenyo’s delivery at the back post.
The home fans made clear their frustration at Maresca’s decision to replace Palmer with Joao Pedro just after the hour mark as the Blues remain in fifth.
Newcastle secured just a second away league win of the season but were made to sweat after a dream start to beat lowly Burnley 3-1.
Goals from Joelinton and Yoane Wissa had the Magpies 2-0 up inside seven minutes.
Josh Laurent halved the arrears midway through the first half and Burnley hit the woodwork twice in the closing stages in their push for an equaliser before Bruno Guimaraes sealed victory for Eddie Howe’s men.
A depleted Everton climbed into the top half of the table by getting the better of former boss Sean Dyche for the second time in a month with a 2-0 win at Nottingham Forest.
The Toffees had not scored since their 3-0 win over Forest on December 6 but struck through James Garner and Thierno Barry to leave Dyche’s men just four points above the relegation zone.
It could have been worse for Forest had West Ham not blown the lead twice to draw 2-2 at home to Brighton. (AFP)
