Just hours after welcoming Manchester United’s record signing Ángel di María, Louis van Gaal’s early woes as manager deepened as his side were dumped out of the Capital One Cup in emphatic fashion by League One side Milton Keynes Dons. It was already a sign of the club’s current predicament that they were playing at this early stage of the Leaguer Cup for the first time in 19 years. And just like in 1995, the Premier League giants were brushed aside by third-tier opposition. In front of a record crowd at Stadium mk, a club formed just 10 years ago celebrated its greatest triumph to date by romping to a thoroughly deserved 4-0 victory over England’s most successful club, thanks to two goals apiece by Will Grigg and Benik Afobe.

After a 3-0 loss to York City at Old Trafford in 1995, United went onto the win the league and cup double at the end of the very same season. On the evidence provided on Tuesday and in the opening weeks of the season, it will take all of Van Gaal’s mastery as well as further signings to complement the arrival of Di María to even come close to repeating that feat in nine months’ time.

Van Gaal made 10 changes to the lineup that drew with Sunderland just 48 hours earlier, fielding a lineup consisting largely of youngsters and players that, if they hadn’t already exhausted their last chance to prove their worth at Old Trafford surely have done now. It was a night when no one in red enhanced their reputation. A young team featuring two debutantes was sent on its way to defeat by its captain and most experienced member when Jonny Evans gifted away possession in his own box and Grigg struck his first. It was to prove no wake up call for United. The second half only got worse as Van Gaal looked on stony-faced when three more goals followed. The third was a goal of real quality and should help ensure that the side which finished mid-table in League One last season are not forgotten in amid the focus on the struggles of England’s most successful club, but defensive calamity was an ever present for the visitors on one of the most chastening evenings in the club’s recent history.

Given that Van Gaal fielded a side featuring few players he will hope to count on this season, it would be in some ways misguided to read too much into the defeat. Yet it is not quite that simple. The performances all-round fell below expectations, particularly those of the team’s more experienced players -- Evans, Anderson, Danny Welbeck and Javier Hernandez. They reflected a far more general malaise that has been allowed to sweep over the club since Sir Alex Ferguson stepped away 15 months ago. Youngsters like Saidy Janko, Reece James and Marnick Vermijl played with immense fear rather than the excitement of relishing their opportunities in the first team.

Evans is at the opposite end of the experience scale and, despite making his first appearance of the season after injury, given Manchester United’s lack of defensive options, his performance in what was again a back three will be deeply disconcerting to Van Gaal. The 26-year-old inexplicably handed the ball straight to Ben Reeves 19 minutes in and the midfielder’s pass found Grigg for a simple finish.

By that point, Shinji Kagawa had already lost his opportunity to impress Van Gaal having gone off with concussion. The Japanese playmaker had actually looked lively before his exit, which largely couldn’t be said for his replacement Adnan Januzaj or Welbeck or Hernandez ahead of him. In midfield, Nick Powell, despite going close with two long-range efforts, looked off the pace alongside Anderson, whose continued place in the squad remains a sign of Manchester United’s lack of progress.

But it was the defense where the most glaring deficiencies laid. Three goals in 21 minutes in the second half emphasized those flaws. Reeves was again the creator just past the hour mark with a fine cross that caught Anderson napping and hanging out a forlorn leg to allow Grigg to nonchalantly chest past David de Gea from six yards.

Afobe then came on to torment United’s back line with his direct running. Reeves bettered his first two assists with a brilliantly disguised pass for his third, to allow Afobe to sweep a first-time shot into the net and secure victory for the underdogs. But Karl Robinson’s side weren’t finished there. With six minutes remaining, Vermijl allowed a simple ball down the line to bounce past him for Afobe, who ran straight through a woeful challenge from Evans, before breezing through another limp tackle and firing low and hard into the corner. It was a fitting end to United’s night to forget.