An injury to Anthony Martial gave 18-year-old Marcus Rashford his debut against FC Midtjylland on Thursday

Marcus Rashford's world changed in 12 second-half minutes on Thursday, when two debut goals in Manchester United's 5-1 thrashing of FC Midtjylland turned the 18-year-old striker from talented teenager into teenage talisman.

Mark Gaynord coached Rashford when he was a five-year-old playing for Fletcher Moss Rangers in Manchester, a club that has already produced the likes of Wes Brown, Danny Welbeck, Cameron Borthwick-Jackson, Ravel Morrison and Tyler Blackett.

He tells BBC Sport what marked Rashford out as special.

A star at five

It did not take long for Gaynord to realise Rashford's unbelievable goalscoring potential.

"We went to a tournament and I took him down there - I watched this lad and in only 10 minutes he had scored 12 goals," said Gaynord. "He kind of got bored so started setting up his team-mates to score and we won the game 20-0 - in 10 minutes.

"He had something special, he was just a naturally gifted footballer and what a nice young lad. There was no big-headedness, his is just the perfect role model for a footballer."

Opposition managers drooled

But it was not just Gaynord who was in awe of the youngster's ability. Other managers wished Rashford was in their colours.

"The other teams would say 'where have you got him from, he's unbelievable'," added Gaynord. "I had the pleasure of watching him week in, week out for four seasons and the other managers would just talk about him.

"He was always getting the Man of the Match award off the other managers so I had to step in and start nominating other players as man of the match."

Coaches learned from him

As well as loving Rashford's talent, Gaynord says the youngster helped his coaches improve and learn new skills.

"He was so far above the other players," said Gaynord.

"His main game was doing the football but he also had a modelling role and his mum would say "he has to go to a photo shoot".

"He would miss two or three training sessions doing photo shoots and come back and show us new stuff. We would work on certain skills and development but he would come in and pick up the skill straight away. But he would not only show the boys the skill, he would show me an advance to it."

'The Lionel Messi of mini soccer'

Argentina's Lionel Messi joined Barcelona aged 13 and has scored more than 500 goals for club and country

After four years of unbelievable goalscoring for Fletcher Moss Rangers, he then joined Manchester United's youth set-up.

"It was no surprise that Manchester United approached me to take Marcus and have him at the development centre," said Gaynord. "It was a pleasure to watch him and work with him for four years until he got signed by United at nine.

"He was good with me, but he was even better once he got to United where he was just untouchable on the pitch. He was like the Lionel Messi of mini-soccer football at 10 years old.

"It's all down to what our coaches are putting in with these lads - it's the start of their ladder," added Gaynord. "We're based on skill and fun and the players move on from there. We've got a good set of coaches with a great team spirit and we encourage the lads."

Hitting the big time

Injuries to Wayne Rooney and Anthony Martial gave Rashford a chance for Manchester United

Rashford had not been expected to start for Manchester United on Thursday in the first leg of their Europa League last-32 tie against FC Midtjylland. However, an injury to Anthony Martial gave the 18-year-old his debut, and Gaynord watched on avidly.

"I had butterflies for him inside and it brought a tear to my eye to see him up front for Manchester United," said Gaynord.

"When he started the game and looked so relaxed on the ball I just thought it was like watching him aged six again. He is still an unbelievable player at this level of football.

"When he put the ball in the back of the net I was in floods. It's one of my proudest moments, apart from seeing my kids born, watching Marcus score for Manchester United.

A new class of '92

It was a dream debut for Rashford, scoring twice as United moved into the last 16.

Rashford joined other United academy products, including Borthwick-Jackson, Jesse Lingard, Paddy McNair and James Wilson, to have featured in the club's first team this season.

Gaynord believes the youngsters could go on to enjoy the same success as the 'class of 92', which included David Beckham, Ryan Giggs, Paul Scholes, Nicky Butt, Gary Neville and Phil Neville.

"Marcus and these young players who are breaking through are the new 'class of 92'," he said. "These players will play for Ryan Giggs and will have the utmost respect for that lad because they know what he has done for that club. Giggs has the class of 2016 in his hands."

Former Manchester United manager Sir Alex Ferguson (left) with the 'class of 92' - Ryan Giggs, Nicky Butt, David Beckham, Gary Neville, Phil Neville and Paul Scholes. The club won the Premier League title 13 times between 1993 and 2013 and the Champions League twice

Keep with Giggs and Van Gaal

"If we keep with Ryan and Louis van Gaal, we're going to have a great squad of youngsters. They will not have to go out and spend £60m on these internationals and European players as we've already got them here on our doorstep."

Former Chelsea manager Jose Mourinho has been tipped to replace Van Gaal in the summer, but Gaynord thinks the club's youngsters will progress better under the current management.

"We have a bunch of talented players who can produce and get into the national side and go and win the World Cup," added Gaynord.

"I'm certainly in the Van Gaal and Ryan Giggs camp. Jose Mourinho is not an academy manager, he has not nurtured players like Sir Alex Ferguson and like how Van Gaal and Ryan Giggs are doing now. For me I want to see home-grown talent."