Yeovil Town 0 Manchester United 2

“We are Yeovil Town, ooh arrr!” went the chorus of “Yeovil True”, the song they once took to 36 in the charts. The supporters here had queued up to 17 hours for a ticket, including one who had flown in from Brisbane especially for the occasion, and for a while they might actually have looked at Manchester United and dared to think they could be ripe for an upset.

There were the three occasions inside the opening 16 minutes when the most expensively assembled group of footballers to roll into town resorted to safety-first football and lumped the ball over the stands. There was the inexplicable moment when Wayne Rooney could be seen putting a straightforward pass out for a throw-in. David de Gea did the same as he tried to find Tyler Blackett and, once again, there were long passages when United's football seemed strangely lost and aimless and Louis van Gaal must have been alarmed by the way his team struggled to keep the ball.

Yet they were wonderful goals with which Ander Herrera and Ángel di María removed any danger of being taken to a replay against the team that is propping up the rest of League One. Herrera took his shot on the turn, letting fly with his right foot to hook a bouncing ball over Jed Steer from over 20 yards. Di María's was from closer range and his delicate finish, after running clear a minute from the end of normal time, was the type that would rarely be seen in English football's third tier.

In those moments, United reminded everyone of the gulf between the two sides. It had, however, taken them a while to get going and there were periods when it was laboured in the extreme. Yeovil had matched them for 64 minutes, leading the public announcer to announce the man-of-the-match award as “the entire team.” Gary Johnson’s team gave everything and they certainly did not look like a side that had just lost three on the bounce to Colchester, Bristol City and Leyton Orient.

What they lacked was the refinement in attack to threaten an upset during those spells when their opponents were struggling for any real momentum.

The spearhead of their attack came in the shape of Kieffer Moore, standing 6ft 5ins tall and wearing a bandage around his head after a collision that also left Paddy McNair patched up for three-quarters of the match. Moore’s first contribution had been to leave his shoulder on De Gea as United’s goalkeeper collected a cross but, at the risk of being cruel, the rest of the striker’s performance brought back memories of Alan Cork’s complaints to his Wimbledon team-mates that he did not want the ball at his feet.

Moore did have all the ingredients to be the classic FA Cup hero, with his background at Dorchester Town and Truro City. Unfortunately for him, when he had Yeovil's best chance 10 minutes into the second half he never showed any conviction from only eight yards out and will probably wince when he sees the replays of his tame shot. The same player also had a chance in the first half to send Kevin Dawson behind the opposition defencebut again took too long to release the ball and the danger was cleared.

Not that it was much better from United at times. The only moment throughout the opening half when United flickered into life came from Radamel Falcao nonchalantly putting Joseph Edwards in his place with a beautifully delivered nutmeg. Otherwise, the Premier League’s third-placed side plodded through the first half. It would be exaggerating to say they were rattled but they certainly did not look comfortable and by half-time the supporters who had filled these stands over two hours before kickoff were entitled to be encouraged. Steer had barely had to make a save.

Van Gaal's alterations during the interval left the distinct suspicion he was entirely dissatisfied with what he had seen. Both his wing-backs, Rafael da Silva and Luke Shaw, were removed and the 3-4-1-2 system was replaced by a flat back four and a midfield diamond. Jonny Evans came on to partner Chris Smalling in the centre of defence, with McNair and Blackett moved to the full-back slots despite being centre-backs by trade.

For the two players who had been taken off, it was another reminder that Van Gaal will have no qualms about hurting their egos if he senses inadequacies.

Yeovil’s attitude was epitomised by the number of times Edwards could be seen snapping into tackles in midfield. Their captain will also reflect on that moment, from the only clear opportunity to make it 1-1, when he sent a header goalwards and Di María, of all people, cleared it from in front of his goal-line. Di María’s arrival as a substitute brought a collective gasp inside Huish Park and his brief contribution explained the reasons for the crowd’s awe.