Manchester United performance against Leicester City must have irritated and confused Erik ten Hag

Manchester United progressed to the quarter-finals of the Carabao Cup thanks to a 5-2 win over Leicester City.

Erik ten Hag was sacked following defeat to West Ham in the Premier League at the weekend and Ruud van Nistelrooy has been placed in interim charge until Ruben Amorim's expected appointment.

United advancing in their pursuit of Amorim has dominated headlines, but there was action on the pitch at Old Trafford on Wednesday night and Van Nistelrooy secured a win.

Leicester are among the favourites to be relegated from the Premier League and struggled against United, who were 4-2 up at half-time thanks to an ironically superb finishing display.

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So without further ado, here are the five talking points from the game...

The perfect response

The United supporters who travelled to the soulless London Stadium on Sunday afternoon were scratching their heads at the interval, wondering how their side weren't leading.

Ten Hag paid the price for the players' wastefulness, losing his job just a day later, and he would have been scratching his head watching United's dominant win against Leicester, wondering why his former players couldn't have finished like that when he was facing the axe.

United somehow managed to score five against Leicester when they struggled so badly to find the net, despite creating plenty of chances, in the first half against West Ham.

Nonetheless, it was the perfect response to a turbulent couple of days and there were two confidence-boosting goals for captain Bruno Fernandes, along with a Casemiro brace.

Diogo Dalot provided an assist for Alejandro Garnacho's goal and that will also do a world of good for the full-back, who has looked a shadow of the player he was last season. United breezed past Leicester through to the quarter-finals of the Carabao Cup, most importantly.

Casemiro renaissance?

When Casemiro was substituted at half-time in the 3-0 hammering to Liverpool at the beginning of September, it seemed his time at the club was over and there was no way back.

Fast forward almost two months and there might be life in his Old Trafford career yet. Casemiro has enjoyed an unlikely renaissance recently, unexpectedly winning back his starting role, and he fired United into the lead against Leicester with perhaps the best goal of his career.

United drew first blood against Leicester thanks to Casemiro's rocket and it only took the Brazilian a moment to look up and decide he would unleash a thunderbolt towards the top corner.

The execution was world-class and Casemiro scored again in the first half, smashing home from close range, which saw his name chanted from the Stretford End.

Casemiro deserves credit for buckling down after being hooked against Liverpool. He has forced his way back into the team and is clearly in strong form as the winter approaches.

The welcome for Van Nistelrooy

Van Nistelrooy enjoyed every moment on the touchline against Leicester and received a brilliant reception from Old Trafford when he emerged from the tunnel for the first whistle.

It seems likely the Dutchman will be in charge against Chelsea again this weekend and that will be an opportunity for him to savour the occasion in a more meaningful contest.

Van Nistelrooy's first game in charge as interim boss would have only been improved by United keeping a clean sheet and he can be proud of the players.

Busy week, Jason?

United technical director Jason Wilcox was having a chinwag with former United player David May just outside the directors' box, which connects to the press room entrance at Old Trafford, before kick-off against Leicester and I managed to ask him whether he'd had a busy week.

Wilcox nodded and responded: "Yeah, busy week." It wasn't exactly the type of response that will be printed on the back pages but it was a response nonetheless.

United's statement on Ten Hag's sacking was just 87 words long and Dan Ashworth's voice was absent. Some perceived the statement to be a tad cold and it was a point of interest that Ashworth wasn't quoted considering he has been on practically every club statement since he was appointed sporting director.

There has been no communication from the club's hierarchy this week and they owe it to supporters to explain their decision on Ten Hag and their imminent appointment of Amorim.

Fitzgerald in the squad

Christian Eriksen was absent from the squad to face Leicester, which opened the door for promising youngster Jayce Fitzgerald to be involved on a matchday for the first time.

United remain at the forefront of youth development and giving academy prospects the chance to be involved with first-team squads demonstrates there is a pathway to make a debut.

Fitzgerald made 20 academy appearances last season and was part of a supremely talented Under-18 side that won the treble. His progress has continued this season - he has started every game for the U18s - and it was great to see him named on the bench.

The incoming Amorim has a brilliant record with young players and promoting talent has been key to his success with Sporting, so that bodes well for his tenure in Manchester.