Greenwood came on for the final few minutes of last season’s Champions League win at Paris St-Germain
One year ago to the day, Mason Greenwood made his competitive debut for Manchester United.
At the age of 17 years and 156 days, Greenwood made history in the 3-1 win against Paris St-Germain by becoming the club’s youngest-ever Champions League player.
Since then records have continued to be broken, goals have been scored, and the plaudits have been plentiful.
Before this Sunday’s Manchester derby, BBC Sport takes a look back at how Greenwood’s first 365 days in professional football have gone.
Into the record books and up there with Aguero
Greenwood followed up his senior debut by entering the record books again on the final day of last season – becoming Manchester United’s youngest starter in the Premier League when he made his full debut against Cardiff City.
Since then, Greenwood has seamlessly adapted to the trials and tribulations of domestic and European football in his first full season as a professional.
He has scored five times in 22 appearances for Manchester United this term and has also chipped in with some important goals in the Europa League and domestic cups with a combined six goals in those competitions.
A total of 11 goals in 39 games this term is a very respectable return for any striker, let alone one playing in their first full campaign as a professional, but Greenwood’s tally is all the more impressive when you consider how little time he has had on the pitch – particularly in the Premier League.
Greenwood has played 647 minutes of top-flight football this season, hitting five goals. That means on average he scores a goal every 129 minutes. Only Southampton striker Danny Ings and Manchester City’s Sergio Aguero can boast a better record.
Sixteen goals on debut and two lethal feet
While it has only been over the past 12 months that Greenwood has become a more familiar name to the average football fan, those who work more closely with Manchester United have been excited about his potential for more than a decade.
The Bradford-born player first caught United’s eye when he was just six after scoring an incredible 16 goals in a 16-1 win for his local team.
“He came to our development centre the night his goals from the weekend had made the local newspaper,” Mark Senior, who used to work at Manchester United’s development centre, told Goal.com.
“I got there a little bit early and Mason was already there in the car park smashing balls against the wall, with both feet. It was incredible.
“I asked him: ‘So, are you this Mason who scored 16 goals at the weekend? Was it a bit easy for you?’ He looked at me and said: ‘If it weren’t for me, we would have lost 1-0.'”
Greenwood (second from left) is one of a number of promising youngsters at Manchester United
Greenwood continued to make an impression in Manchester United’s youth teams with his technical ability in particular standing out. The teenager was equally comfortable scoring with both feet and it was the same in other areas of his game – corners, free-kicks and penalties – he took them with whichever foot he felt like.
This rare strength meant members of the first team would apparently share videos of the things Greenwood was able to do with the ball in the dressing room, while also making time to go to youth team games and training sessions to see him in action for themselves.
“Mason is a joke,” Manchester United full-back Luke Shaw said recently. “He uses both feet. Sometimes he’ll take a free kick with his right, then a corner with his left and like with penalties he takes them with whatever foot he feels like that day, whatever he feels like doing.
“When he first came into training and he was doing that, the lads were like ‘what’s this guy doing?’ None of us really knew and we were obviously shocked and it just shows the ability he has.”
How has he compared to past Man Utd debutants?
Federico Macheda, Danny Welbeck and Marcus Rashford all came through the youth ranks at Manchester United
It is very easy to get excited about a young star rising through the Manchester United academy, particularly after the success story of the famous Class of ’92.
However, not every player ends up being the next David Beckham or Ryan Giggs.
Like Greenwood, Federico Macheda boasted a strong record at reserve level that caught the eye of the first-team management. A run of eight goals in eight games in the 2008-09 season earned him a call-up to the senior squad by then manager Sir Alex Ferguson for a game with Aston Villa on 5 April 2009.
After coming on just after the hour mark, he curled in the decisive goal in a 3-2 win in the third minute of stoppage time.
Macheda scored again in Manchester United’s next game – a 2-1 win at Sunderland but was never again able to hit those heady heights. He scored two further goals for the club and had several loan spells before leaving for good in 2014.
Danny Welbeck also enjoyed an impressive breakout campaign.
He scored three goals in 13 games in his first full season and went on to establish himself as important first team player, making more than 30 appearances in three of the next four seasons but injury hampered his ability to realise his full potential before he was sold to Arsenal in 2014.
The most obvious recent success story is Marcus Rashford. He marked his Manchester United debut with two goals against Midtjylland in the Europa League on 25 February 2016 and then hit another double on his Premier League debut three days later in a 3-2 win against Arsenal.
Rashford finished that season with eight goals in all competitions and then scored 11 in his first full season for the club. To date, Rashford has scored 64 goals in 201 appearances for Manchester United.
What next for Greenwood?
Solskjaer believes Greenwood has the potential to become a ‘complete number nine’ for Manchester United
Big things are predicted for the teenager and, given how his rise to prominence has gone so far, there is no reason why he could not develop into a key player for club and country in the years to come.
His development is still ongoing and in a rare start away from home against Everton last-time out, he struggled to have an impact on the game.
But United boss Ole Gunnar Solskjaer is confident that the only way is up for Greenwood.
“He is just going to be better and better,” he said after the teenager scored his latest goal in 3-0 win against Watford on 23 February.
“In a couple of years’ time he will be more or less the complete number nine.”
The most immediate target, however, will be a start in Sunday’s Manchester derby.
Getting the winner in that would only strengthen Manchester United fans’ belief that they have a potential club legend in their ranks.