Axel Tuanzebe (left) and Mason Greenwood (right) have represented England's youth teams

After five summers of pursuing big-name signings and failing to recapture previous glories, Manchester United have embarked on a different strategy under Ole Gunnar Solskjaer.

United are aiming to go back to their roots by investing in youth and giving younger players a chance.

This is an approach embedded in the club's tradition. They have, after all, named at least one academy graduate in every matchday squad since October 1937.

Focusing on home-grown talent is not without risk.

But United see that approach - combined with the occasional significant purchase - as the only realistic way of catching Manchester City, in particular over the long term.

There are signs of this new strategy already. On United's pre-season tour of Australia and Asia, two home-grown talents in particular are signalling that they can meet the challenge - Mason Greenwood, 17, and Axel Tuanzebe, 21.

Greenwood giving Solskjaer 'Giggs memories'

Greenwood's attitude could hardly have been more different from that of team-mate Romelu Lukaku over the past two weeks.

For nearly 40 minutes on Friday, Lukaku sat on the United bench, his personal fitness work done, staring into space as his team-mates went through another tough training session in sweltering heat and humidity.

On the pitch, Greenwood was going about his work, making an impression doing drills and in small-sided games.

Lukaku has missed all three games of United's tour so far. Greenwood has played three. He has scored twice, including the winner against Inter Milan in Singapore on Saturday.

After his previous goal against Leeds in Perth, Solskjaer said he was considering the 17-year-old as a starter for the Premier League opener against Chelsea on 11 August.

The only mention for Lukaku in connection with Chelsea during this tour has come from Antonio Conte. The Inter Milan boss said during a press conference that he tried to buy the striker when he was in charge at Stamford Bridge.

Greenwood, like Tuanzebe, grew up in the United academy. Last season, he was named the club's Young Player of the Year, following in the centre-back's footsteps.

The forward has always scored goals, most notably striking a hat-trick as Chelsea's five-year run as FA Youth Cup winners was ended at the third-round stage last December.

Greenwood is not quite as quick or as strong as Marcus Rashford, but is regarded as a more instinctive finisher. Rashford himself said the Bradford-born forward has "frightening natural abilities".

Not only did he score against Inter Milan, Greenwood also hit the bar. The ease with which he has slotted into United's first-team squad is startling.

It was put to Solskjaer that the striker might be sent out on loan this season to gain experience. The manager could barely conceal his incredulity.

"A loan for Mason has never been on my mind," Solskjaer said. "We have to keep him at our place and play him when we feel it is good for him. At the moment he is flying."

There are bigger names at United, but it is conceivable that Greenwood might be ahead of Alexis Sanchez in the pecking order when the Premier League season starts. Sanchez is the bigger name, but his best performances since joining United have been for Chile.

Solskjaer indicated that Greenwood's progress to the senior set-up is reminiscent of the progress of Ryan Giggs, who made his debut as a 17-year-old against Everton in March 1991, and went on to win 13 Premier League titles over 23 years as a player at Old Trafford.

"He reminds me a little bit of the Giggsy story," Solskjaer said. "You can't really send him on loan.

"The kid's only 17 and he's learning every day. He's grown in confidence and grown in stature. When you've players performing, it's difficult to keep them out.

"We've got to keep our feet on the ground with him and there will be ups and downs but he's enjoying his football he's ready to be in this squad."

'Tuanzebe is the future of Man Utd'

Manchester United have five senior centre-halves with them on tour and they are trying to sign another - potentially England international Harry Maguire, but there are other options if Leicester's valuation remains too high for the Old Trafford hierarchy.

Saturday's match against Inter Milan was the first time in pre-season that Solskjaer let his players stay out on the pitch for more than 45 minutes.

This was the day, one United source said before the game, when Solskjaer's squad would begin to see if they were part of his long-term vision. So it was significant that Tuanzebe was picked alongside Victor Lindelof, ahead of four senior international central defenders.

Born in the Democratic Republic of Congo, the 21-year-old's potential has been known for some time.

Former United academy director Paul McGuinness took the unusual step of naming Tuanzebe as captain of the club's Under-18 side when he was a first-year scholar, something only Gary Neville has managed in recent times.

In 2014-15 he emulated another home-grown central defender in Wes Brown by being named United's Young Player of the Year.

Although Tuanzebe can play at right-back, it is in central defence where he has made rapid progress over the past 12 months. On the United bench at 17, Tuanzebe made his senior debut at 19.

His progress came as Jose Mourinho, United's then-manager, was grumbling about not getting support in the transfer market.

It was just under a year ago that Mourinho was grumbling over not getting another centre-half, having signed one - Eric Bailly and Lindelof - in each of the previous two summers. Yet Tuanzebe was forging a name for himself at Aston Villa.

He lost four months of last season to a foot injury but excelled before and after at Villa Park, under Steve Bruce and the man who replaced him as manager, Dean Smith.

He started both legs of the Championship play-off semi-finals against West Brom - and at Wembley as Villa beat Derby to secure a return to the top flight.

Tuanzebe is quick and good in possession. At Aston Villa, they worked on his awareness. It was interesting in Singapore to see captain Nemanja Matic have a quiet word about his positioning.

Solskjaer is intent on reshaping a defence that conceded 54 league goals last season, the club's highest goals-against total in a single campaign since 1978-79.

Many observers imagined that Tuanzebe would be loaned straight back to Villa this season. Solskjaer, who spent £50m on the youthful defensive talent of Aaron Wan-Bissaka in June, would seem to have other ideas.

"He's got a future at Manchester United," said Solskjaer. "Inter Milan was a test for him playing against different opposition. He's shown he's very capable of playing at this level. Axel is going to be the future of this club."