MANCHESTER, ENGLAND - AUGUST 27:  Lucas Moura of Tottenham Hotspur (hidden) celebrates with team mates after scoring his second goal and his team's third goal during the Premier League match between Manchester United and Tottenham Hotspur at Old Trafford on August 27, 2018 in Manchester, United Kingdom.  (Photo by Clive Mason/Getty Images)

4 Things We Learned as Spurs Stunned Manchester United in Old Trafford Thriller

​Manchester United have lost two of their opening three ​Premier League games for the first time since 1992, as ​Tottenham shocked Old Trafford with a rampant second half display ensuring all three points traveled back to London.

Two goals in quick succession from Harry Kane and Lucas Moura gave Spurs a comfortable lead at the start of the second half, before Moura added to his tally later on with a fine individual goal.

​Here is what we learned from Monday night's encounter... 

4. Lukaku's Misfiring Costs United Again

After a fairly successful World Cup, many thought Romelu Lukaku would be likely to build on his 27 goals in all competitions last season for the Red Devils...but he quite clearly hasn't. 

After a disappointing display against Brighton last week, the striker had a chance to put it right against Spurs. He was given a glorious opportunity first half when a mishit backpass from Danny Rose saw the Belgian round Hugo Lloris, only to fire wide from a fairly tight angle. 

With United losing comfortably, many will look back on Lukaku's miss as a potential game changer as the Red Devils produced an abysmal second half performance.   

3. Lucas Moura Can Replace Son Heung-min

When Lucas Moura arrived on Wembley Way last January, he was expected to be a rotation option at best. 

With Son Heung-min away at the Asian Games, Moura has had to step in for the South Korean, and it's fair to say the Brazilian has made a brilliant start to the season. 

The winger scored his first Premier League goal against Fulham last week, and has now trebled that tally with his brace on Monday night. 

The former PSG man ran the Red Devils' defence ragged,  scoring a lovely goal from 12 yards out before showing some individual class which saw him race away from defender Chris Smalling before finishing clinically past David de Gea. 

2. Tottenham Could Well Be Title Contenders

Many questioned Spurs chairman Daniel Levy over the club's lack of transfers this summer, but the north London side don't look the worse for their lack of additions thus far. 

With no major injury concerns, they are able to perform at the best of their abilities and, with this young side growing, they may well be able to put a title challenge together...if everyone stays fit. 

With their first win at Old Trafford since 2014, Spurs will be brimming with a confidence which could prove vital for a title charge, as Manchester City showed last season.

1. Mourinho Needs to Sort Out United's Problems Fast

It's clear to see the discontent amongst United and their fans right now, with Jose Mourinho at the centre of the problems.

The Portuguese manager has found things difficult so far this season, with a poor transfer window adding to the pain of United's two defeats in their first three games. 

The relationship between chief executive Ed Woodward and Mourinho seems to be causing tension throughout the whole club, with the latter unimpressed with the club's transfer strategy this summer.