Neither Manchester City nor Manchester United typically need to pay much attention to the League Cup, but with both suddenly struggling under their new high-profile managers, Wednesday's derby in the competition became a lot more pressing, and it's the Red Devils who are breathing a little easier.
Juan Mata's second-half goal held up, as United defeated City 1-0 to advance to the quarterfinals.
Jose Mourinho's Man United was 4-4-2 in its last 10 matches and entered Wednesday's match on the heels of a 4-0 loss at Chelsea, while Pep Guardiola's City extended its winless streak to six matches (0-3-3) after starting the new era at the Etihad off with 10 consecutive victories.
City had taken the first meeting between the clubs this season, winning 2-1 at Old Trafford on goals from Kevin De Bruyne and Kelechi Iheanacho.
It was Iheanacho who had a chance to put Man City up in the second minute of the rematch, but his diving header off a laser of a cross was put well over the bar:
Zlatan Ibrahimovic, who scored for United in the league meeting, had a clear look denied in the 36th minute, after Paul Pogba had a cutback pass skip off his foot into the Swedish forward's path, only for the blast from the edge of the area to be blocked.
It was later Pogba's time to be denied, with a sliding Willy Caballero getting just enough of the ball to deflect it off the post minutes into the second half.
Juan Mata provided the breakthrough in the 54th minute at last, finishing off a pass from Ibrahimovic that slid through the box following a collision in the area to give United the lead:
Ibrahimovic tried to play spectacular provider a little later on, with his sensational back-heel pass failing to find Marcus Rashford, who got a little tangled in the Manchester City box and couldn't run onto what surely would have been a clean look at goal:
Manchester United joins Arsenal, Liverpool, West Ham, Hull City, Leeds United, Newcastle and Southampton in the final eight of the competition.
The Red Devils turn their focus to hosting Burnley this weekend, while City plays at West Brom, looking to get back to its winning ways.