#3 Mason Greenwood
Mason Greenwood was one of the revelations of the 2019-20 season, and it was expected that he would build on this to become a mainstay in the team.
However, the England international had a mixed campaign last term and lacked the confidence he exhibited in his breakout season.
He underwent different goal droughts, and his season ended on a sour note when an injury forced him to miss the European Championship with England.
Greenwood will be hoping to put all that behind him, and the ongoing pre-season campaign offers him an excellent opportunity at a clean slate.
The absence of several first-team stars means that the 19-year-old finds himself as one of the more experienced players in the training camp, despite still being a teenager himself.
#2 Shola Shoretire
Shola Shoretire made history for Manchester United when he became the youngest player to make an appearance in a European competition for the club.
He was just 17 years and 23 days old when he replaced Mason Greenwood in the Europa League clash with Real Sociedad, breaking Norman Whiteside's former record by 108 days.
Big things are expected of the 17-year-old, and an impressive pre-season display could speed-track his promotion to the first team.
Manchester United have a long and proud history of giving opportunities to young players. Whether Shola Shoretire can join an illustrious list that includes Ryan Giggs, Duncan Edwards, Cristiano Ronaldo and Marcus Rashford remains to be seen.
#1 Jesse Lingard
Jesse Lingard is arguably the Manchester United player with the most to prove, and this makes him the player to watch out for the most.
The 28-year-old came through the Manchester United academy. He was initially a mainstay in the first team before paying the price for his inconsistencies with extended spells out of the squad.
By the end of the 2019-20 season and the start of the 2020-21 campaign, Lingard was something of a forgotten man at Old Trafford and was left out of several matchday squads.
A loan transfer to West Ham was agreed in January 2021, and the 28-year-old instantly adapted to his new environment like a fish to water. A remarkable turnaround saw him contribute nine goals and four assists from his first 10 Premier League games for the Hammers.
His form saw him named the Premier League Player of the Month in April and also earned him a recall to the international scene after an absence of almost two years.
Jesse Lingard remains determined to break into Manchester United's starting lineup, and this will serve as motivation for him to give his all during pre-season.
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