Manchester United players celebrate during their win over Aston Villa at Old Trafford in Manchester, England, November 10, 2022. /CFP
Bruno Fernandes sent Manchester United into the League Cup last 16 as the Portugal midfielder punished a howler from Aston Villa keeper Robin Olsen in Thursday's 4-2 win.
Erik ten Hag's side were in danger of losing to Villa for the second time in a week after trailing twice in the third round tie at Old Trafford.
Beaten 3-1 by Villa in the Premier League last weekend, United fell behind to Ollie Watkins' second half opener.
Anthony Martial equalized but Diogo Dalot's own goal restored Villa's lead in their second match under new boss Unai Emery.
Marcus Rashford hit United's second equaliser and Fernandes put them ahead after Olsen's woeful pass went astray before Scott McTominay wrapped up the victory in stoppage-time.
Ten Hag had said he wanted a "reaction" after branding United's limp loss at Villa Park as "not acceptable".
The United manager got his wish, but not before a scare from Emery's team, who have played with more verve since the Spaniard arrived from Villarreal to replace the sacked Steven Gerrard.
"Happy with that resilience. That's what we need and have to show every game. I was so disappointed and mad on Sunday because we didn't fight," Ten Hag said.
Scott McTominay of Manchester United scores the fourth goal during their win over Aston Villa at Old Trafford in Manchester, England, November 10, 2022. /CFP
The League Cup remains United's last domestic trophy triumph in 2017 and Ten Hag would relish the chance to end that drought later this year.
He will have to wait until after the World Cup for United's next League Cup tie against Burnley, with the last 16 scheduled for just days after the final in Qatar.
Holders Liverpool have been handed a trip to Manchester City in a high-profile last 16 clash, but both teams are likely to feature youthful line-ups to allow their players extra rest after the World Cup.
Elsewhere, Toni Kroos scored a goal and set up one for Eder Militao as Real Madrid beat second-bottom Cadiz 2-1 in their last LaLiga match before the World Cup break.
The champions returned to winning ways after losing 3-2 to Rayo Vallecano on Monday, their first league defeat of the season, and are second in the standings on 35 points, two behind leaders Barcelona.
Earlier on Thursday, Gennaro Gattuso's Valencia beat 10-man Real Betis 3-0 to end their five-game winless streak.
Betis, who could have climbed to third in the standings with a win, are now sixth on 24 points. Valencia are 10th on 19.