The English League Cup cannot make a season for a top team, but it could make matters a lot worse for a stuttering side. Following indifferent league form and Sunday’s 4-0 hammering at Chelsea for which manager Jose Mourinho apologised to fans in his programme notes, Manchester United could not afford to lose against neighbours Manchester City. Pep Guardiola’s side had already won convincingly at Old Trafford in the September derby. Another City victory would have depressed the mood among United fans further, the optimism of August’s winning run now long gone as a league position of sixth or seventh is the new reality of post-Alex Ferguson life at Old Trafford. The circumstances were similar a few months after Ferguson departed in 2013. United had been hammered 4-1 at City in a September derby match before a League Cup game at home to another huge rival, Liverpool, three days later. United scraped a 1-0 win against their rivals to bring temporary respite in a difficult season. <strong>More football:</strong> <strong>• Steve Luckings: </strong><a href="http://www.thenational.ae/sport/english-premier-league/the-answer-to-jose-mourinhos-paul-pogba-problem-at-manchester-united-is-simple-michael-carrick">The answer to Jose Mourinho's Paul Pogba problem is simple: Michael Carrick</a> <strong>• Premier League predictions: </strong><a href="http://www.thenational.ae/sport/english-premier-league/man-united-bounce-back-in-style-southampton-provide-stern-test-for-chelsea--premier-league-predictions">Big wins in store for Manchester United, Arsenal, and Manchester City</a> <strong>• The Big Weekend Preview: </strong><a href="http://www.thenational.ae/sport/football/the-big-weekend-preview-can-man-city-arsenal-liverpool-chelsea-or-spurs-stamp-their-mark">Can Man City, Arsenal, Liverpool, Chelsea or Spurs stamp their mark?</a> <strong>• Greg Lea: </strong><a href="http://www.thenational.ae/sport/english-premier-league/arsenal-despite-middlesbrough-setback-in-safe-hands-for-sustained-premier-league-title-tilt">Arsenal, despite Middlesbrough setback, in safe hands for sustained Premier League title tilt</a> The derby game at Old Trafford on Wednesday offered a similar chance to bounce back and, in front of a sell-out 75,196 crowd which included 8,000 City fans, United took it. City made nine changes from their team which had drawn against Southampton at the weekend, fielding a far weaker side — albeit one stocked with international players. Guardiola claimed that he needed to rest players after finishing against Barcelona away with 10 men and with a home Uefa Champions League game against the Catalans next week. His priority is not the League Cup and while he cut a confident figure after the match, his side have not won in six — his worst record since becoming a manager. The biggest clubs often use the League Cup to field younger or emerging players. United legends David Beckham, Paul Scholes and Mark Hughes all made their debuts in the competition, and while City had space for two 19-year-old Catalans — but no English players in their starting XI — United went with their big guns. Pablo Maffeo and Aleix Garcia both made debuts and were City’s best players. Their compatriot Guardiola rightly said he was proud of them, yet his side otherwise offered little and didn’t have a single attempt on goal. Such was the need to get a win, United couldn’t afford to chance youth or even peripheral players. Argentina’s first choice goalkeeper Sergio Romero may have expected to start another League Cup match, but Mourinho needed a win more than Guardiola. The Portuguese tweaked his midfield, with the seldom used Michael Carrick and Ander Herrera joining Paul Pogba. It worked. Ahead of them, Juan Mata influenced another match, scoring a deserved 54th minute winner. A favourite to be sold when Mourinho arrived, the Spaniard remains one of United’s most important players. He runs, he scores, he assists and, in that best Spanish tradition, is always available to receive the ball. Carrick, 35, who has not disappointed when called upon, sat in front of the back four and showed the experience United were missing at Stamford Bridge. By the 85th minute and with United winning, fans sang: “It’s hard to believe it’s not Scholes, it’s Carrick, don’t you know.” Mourinho was also rewarded in song by fans who are firmly behind him, but his honeymoon period is over. His team need to keep on winning and not only against weaker opposition. He also needs to find his best side, but he will have been encouraged by his midfield, if not his leading striker Zlatan Ibrahimovic. The Swede did make his first assist of the season and was involved in a couple of impressive moves, but, after a bright start to the season, doesn’t look close to being the player United hoped he would be. He has the talent to regain his form. Next up for United in the league are strugglers Burnley and Swansea City. Mourinho will be looking for his team to build on the confidence gained from defeating City to close the gap between seventh and the top of the table. Another home draw against West Ham in the quarter-final favours United in a competition they used to use to give youngsters minutes and experience. Now, it’s much more important than that. <strong>Follow us on Twitter </strong><a href="https://twitter.com/NatSportUAE">@NatSportUAE</a> <strong>Like us on Facebook at </strong><a href="https://www.facebook.com/TheNationalSport/">facebook.com/TheNationalSport</a>