Tottenham suffered a third successive 1-0 defeat at Old Trafford as Anthony Martial came off the bench to net an 81st-minute winner. Here are five Tottenham talking points.

1. Eric Dier is chosen instead of Davinson Sanchez in central defence

Mauricio Pochettino likes to spring surprises with his selections, and he again kept everyone guessing for a while after announcing his line-up and revealing he was leaving Davinson Sanchez on the bench.

One theory in the hour before kick-off was that he was switching to 4-2-3-1, but instead Dier moved into the centre of the rearguard, between Toby Alderweireld and Jan Vertonghen.

Interestingly, Jose Mourinho revealed during the summer when his side faced Ajax in last season’s Europa League – an Ajax side including Sanchez – he told his players to allow the Colombian to have the ball.

“We would let them play out from the back while blocking De Ligt, their right centre-back, making them play through Davinson Sanchez, who had more trouble,” said the Portuguese in June.

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Pochettino claimed not to have seen that comment when he was asked about it on Friday, but was that the reason for Sanchez’s omission – because the Spurs manager expected similar tactics from Mourinho again? Or was it because he felt Dier has more experience and would be stronger in the air against Romelu Lukaku?

Either way, Pochettino’s decision looked justified for the vast majority of the match. Dier was indeed allowed time on the ball and generally used it well, even leading one attack and slipping a pass to Heung-Min Son on the edge of United’s box.

And, after being beaten by Lukaku in the air and on the ground in their first two duels, he quickly improved and largely got the better of the big Belgian, while making several important interceptions and trademark tackles.

It was therefore a real shame that Dier was largely at fault when United grabbed their decisive goal in the closing stages, allowing Anthony Martial to run in behind him and beat Hugo Lloris.

2. Spurs lack cutting edge in absence of Harry Kane

Spurs spent £14million in the summer to bring in the experienced Fernando Llorente as back-up for Kane.

The Spaniard had started against Real Madrid at the Bernabeu and been withdrawn in the 72^nd minute of Wednesday’s League Cup tie against West Ham, so it seemed reasonable for some to expect him to start this match. However, Pochettino opted to deploy Son up front at Old Trafford.

It made sense. Apart from a couple of neat early flicks, Llorente had offered little against the Hammers, and his lack of mobility can make him easy to mark.

It is doubtful whether his physicality would have particularly unsettled Phil Jones and Eric Bailly, who are a sturdy pair, and it seemed reasonable to expect that Son’s pace and movement would cause United’s defensive duo more problems.

The South Korean was ultimately unable to make a telling impact, though, despite his industry, and was taken off just after the hour-mark. His replacement Llorente was then unable to do much better and Spurs were left to rue the injured Kane’s absence as they drew a blank.

3. United land the killer blow as the game opens up in closing stages

As the final 15 minutes arrived, it seemed this match was going to end in a repeat of United’s stalemate at Liverpool a fortnight ago, with the defences taking the paludits.

However, both sides then created their best chances of the encounter. Christian Eriksen, who was generally kept quiet and struggled to exert his usual influence, finally unlocked the United defence with a floated pass which freed Dele Alli behind Chris Smalling, but Alli prodded wide from six yards. Moments later, Lukaku rose above Toby Alderweireld and headed against the post at the other end.

A showdown which had apparently been meandering towards a draw had now come to life – and it was United who landed the decisive punch, capitalising on poor Tottenham defending.

When David de Gea launched a routine ball downfield, Alderweireld – for the second time in the space of a few minutes – failed to get off the ground and challenge Lukaku in the air. The result was a flick-on, and substitute Martial wriggled in behind Dier for too easily before slotting past Lloris.

Having competed so strongly for so long, two moments at either end – Alli’s miss and the failure to defend a simple long ball – proved hugely costly for Tottenham.

4. History repeats itself at Old Trafford

Spurs have undoubtedly made great progress in recent seasons but they left Manchester with a feeling of déjà vu – this was their third successive 1-0 loss at Old Trafford, and their fourth defeat in a row here in all.

While Pochettino’s Lilywhites are repeatedly beating their top-six rivals on home turf, they continue to leave the stadiums of their biggest foes empty-handed, even if the margins are fine.

Tottenham have now slipped three points behind United in the table, and league leaders Manchester City can move eight points clear of them today.

5. On the bright side, Harry Winks continues to grow in importance

Not so long ago, the absence of Mousa Dembele from the starting line-up would have been a great cause of disappointment for Spurs fans. Not any more.

In Harry Winks, they have a prodigious alternative and the 21-year-old is fast becoming an automatic starter in his own right.

Having recently been picked in the initial XI against both Real Madrid and Liverpool, he again embraced the occasion today and was soon showing his qualities against United’s expensively-assembled side.

Although he was pressured into sending an early pass out of play deep in his own half, he quickly grew in confidence and turned a similarly tight situation into a bursting run upfield.

That moment set the tone for the rest of his performance and he again looked right at home on the big stage with his immaculate ball control, quick and positive passing and diligence out of possession.

When Dembele was summoned from the bench just after the hour-mark, Pochettino tellingly withdrew Moussa Sissoko rather than Winks.

The youngster, who did not deserve to be on the losing side today, is rapidly carving out a valued role for himself while justifying all the faith shown in him, and his performances in this series of high-profile clashes against Champions League sides can only boost his hopes of being named in the senior England squad again for the upcoming internationals.

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