Greenwood must improve his heading ability, according to coach Solskjaer | DeFodi Images/Getty Images

Manchester United boss Ole Gunnar Solskjaer has urged attacking starlet Mason Greenwood to focus on his heading ability in order to become the perfect, all-round number nine.

The 18-year-old came on as a late substitute in the Red Devils' 3-0 victory over Luton Town on Tuesday night, scoring the final goal of the game with a lovely cut inside from the right flank.

Solskjaer praised Greenwood's ability to play out wide or centrally after the Carabao Cup progression, but the Norwegian believes the youngster's future lies as a number nine, rather than a winger.

However, he's not the finished article in his boss' eyes. Speaking after the game, Solskjaer explained that the forward must 'learn how to head a ball', urging him 'to come and practise' his technique with the 'baby-faced assassin'.

“The goal was important for him and Marcus (Rashford), always as strikers. To get that confidence and feeling of scoring. Mason can play through the middle and also wide. Sometimes, it is nice to be out wide facing forward rather than being the number nine and battering ram. I think he will end up as a number nine.

Greenwood celebrating a strike in last season's Europa League | Pool/Getty Images

“But for him to be a number nine, he needs to learn how to head a ball. I keep telling him that. If he wants to do that he is welcome to come and practise with me.”

Greenwood burst onto the scene for the Red Devils last season, initially making his mark in the Europa League, before becoming a regular in the lineup upon football's re-start. The England international hit 10 goals in the Premier League and five in Europe, helping Man Utd clinch a Champions League qualification spot, and a run to the semi-finals of the Europa League.

The teenager is learning his trade under one of the most clinical forwards in top-flight history in Solskjaer, who was known for his ruthless nature in front of goal - with every part of his body. The opportunities are there then, for Greenwood to hone his skills and become the ultimate number nine at Old Trafford.