As Manchester United were labouring to a goalless draw at AZ Alkmaar in the Europa League, a player they once had on trial was hitting in two goals in two minutes in the same competition for Arsenal.

Exciting teenager Gabriel Martinelli made it four goals in just two starts for the Gunners as they thumped Standard Liege 4-0.

The 18-year-old was the top trend worldwide at one point on Thursday evening, highlighting the buzz around the talented forward tipped to be the next Brazilian superstar.

Some people were getting carried away...

REALLY carried away...

But there is no doubting Martinelli has made an exciting start to his Arsenal career, not bad for a player who cost the Gunners just £6m in the summer and initially had many of the club's fans asking: "Gabriel who?"

The boy from Brazil tipped to be the next big thing

Martinelli has been tipped to follow in Neymar's footsteps and become a big star for Brazil

Few fans had heard of Martinelli when he became Arsenal's first signing of the summer, joining from Brazilian club Ituano in July.

However, back in his homeland he is viewed as having the potential to become as big as Neymar and he has certainly made an impression in his short time at Arsenal so far.

He has started two games for the club: in the 5-0 win against Nottingham Forest in the League Cup and Thursday night's game against Standard Liege, and bagged two goals in both.

In all his appearances so far, Martinelli has caught the eye with his quick feet and close control. Like compatriot Philippe Coutinho, those skills were honed by playing futsal as a youngster. He was part of Corinthians' futsal team from the age of nine until 14, when he joined fourth division Brazilian team Ituano in 2015.

Martinelli, like many teenagers, grew up idolising Portugal star Cristiano Ronaldo and claims to model his game on the Juventus forward.

Emery hails 'hungry' Martinelli

Arsenal boss Unai Emery is excited about what Martinelli can achieve at Arsenal, but he's not getting carried away.

"The first thing in his mind is to help us," he said after Thursday's Europa League win.

"In the pre-season he was perfect, all the time with us. I spoke with him to be calm because when his opportunity arrives if he continues with that hunger he is going to do well.

"His pace is amazing. Above all he prefers to play left winger. I am using him as a striker because he played in that position in Brazil."

The one that got away?

Martinelli has previously been invited to train with the Brazil senior team

In an interview with ESPN Brazil earlier this year, Martinelli revealed he had a number of trials with Manchester United over a two-year period from 2015.

According to the Manchester Evening News, external-link the then 14-year-old played alongside Mason Greenwood in a friendly for United's youth team against Lincoln's Under-18s. United won the game 2-0 but the Red Devils ultimately decided not to follow up their interest.

"Between 2015 and 2017 I went there four times and trained on average about 15 days," Martinelli said. external-link

"I saw all the professionals. I asked to take a picture with [Patrice] Evra, [Marouane] Fellaini and other guys. [Paul] Pogba knew I was Brazilian and asked if everything was fine with me and where I played. We took a picture together."

Belgian side Gent and Spanish giants Barcelona also had a look at the player before Arsenal made their move to bring him to Europe.

They're not the only ones

Only time will tell whether Arsenal have truly got one over on a rival by signing Martinelli. But football is littered with tales of clubs passing up on players only for them to enjoy stellar careers elsewhere, and the Gunners are no exception.

Back in 2016, they sold Serge Gnabry to Werder Bremen for £5m. The forward was back in London earlier this week with Bayern Munich as he scored four goals in a 7-2 Champions League demolition of Arsenal's rivals Tottenham.

Another former Arsenal youngster Donyell Malen scored twice as PSV won 4-1 at Rosenborg in the Europa League on Thursday. The 20-year-old has scored 12 goals in his past eight PSV games, as well as netting on his Netherlands debut against Germany.

It happens to the best of us...