Scott McTominay made his 15th appearance for the first team this season in Manchester United's 2-1 win over Chelsea on Sunday, as Jose Mourinho has opted to maintain the club's tradition of incorporating youth team players in the first-team squad.

McTominay made his debut at the end of last season when Mourinho had given up all interest in accruing more league points in preference for chasing European glory and automatic Champions League qualification. His first 90 minutes came on the final day of the season, as United managed to beat Crystal Palace 2-0, despite putting out a team largely consisting of academy graduates.

Four of the players in the squad that day have since gone out on loan, while goal scorer Josh Harrop left for Preston North End on a permanent deal in the summer. McTominay managed to stick around, though expectations weren't high for him making a name for himself at the club.

"Last season, was almost leaving the club to go somewhere, who knows where, who knows in which division he'd be playing now," Mourinho recently said of McTominay, following his inclusion in the starting XI for United's win over Huddersfield in the FA Cup, at the expense of Paul Pogba.

A few years ago, McTominay was interviewed by the official club website about his ambitions when it came to international football. He was born in England but has lots of Scottish family members. Having been involved in some of the Scottish youth camps but never playing for either country at youth level, he leaned toward the likelihood of playing for Scotland. Yet the people who read that interview in 2016 would have been forgiven for suggesting that he would never be good enough to play for either. He wasn't making any lists of players to keep an eye out for.

However, that topic arose again last week after McTominay further established himself in United's first team after starting against Sevilla in the Champions League round of 16.

The midfielder's stock continued to rise following his performance in United's win over Chelsea. It was a performance that exposed his biggest flaws as well as some of his greatest strengths.

Either through inexperience or a lack of awareness, McTominay stopped tracking Willian's run in the first half, which allowed Chelsea to take the lead. However, United were able to get back into the match and eventually win it because Eden Hazard was marked out of the game by the youngster.

Antonio Conte revealed that his decision to substitute Hazard in the 73rd minute was a tactical one. While McTominay was humble in his response to being asked about how he felt contributing to Hazard's lack of impact on the game, it says a lot about his ability to follow Jose Mourinho's instructions that the Belgian was so anonymous at Old Trafford. Ander Herrera performed the same task in United's 2-0 win against Chelsea last season, yet when you consider that McTominay had made only 17 first-team appearances, it speaks volumes of his self-belief and ability to be able to nullify one of the league's best players.

Scott McTominay has been thrust into an unlikely squad role at Man United and has seized the opportunity. Photo by Pedro Salado/Action Plus via Getty Images

Lovingly referred to as "the kid" by Mourinho, some fans have already made some comparisons with this manager-player relationship and that of Sir Alex Ferguson's with Darren Fletcher. For years United supporters couldn't understand what Fergie saw in the Scotsman, but in the end, he more than proved his worth to the club.

The difference between them is that Fletcher showed huge potential when in United's academy, particularly before a string of injuries hampered his development, while McTominay never set the world alight at youth level.

The best players to come through United's academy have usually shown glimpses of what they might be capable of on the big stage, whereas McTominay has largely gone under the radar to this point.

Some United fans have already written him off, while others are hailing him as a huge talent, but the majority are reserving judgement, as they should. Although the eight hours of playing time in the league and Champions League is more than they would have expected him to get, especially from Mourinho who was supposed to be "the monster that kills the little kids," it isn't enough to form a conclusive opinion yet.

Nemanja Matic, a player whom McTominay should aspire to be like, has often spoken well of the youngster. In November, he hailed his talent and work ethic. The following month, he tipped him to become a "big player" for club and country.

Mourinho has repeatedly lavished praise on the youngster too, and given his usual preference for established and experienced players, it speaks volumes that he has given so much playing time to the youngster of late.

Andreas Pereira, who is having a good season in Spain with Valencia, might well be looking on and wondering what might have been, had he listened to Mourinho's advice and stayed in Manchester.

But when your chance comes, you have to take it. Marcus Rashford did exactly that two years ago, when he was thrown into the starting lineup in the Europa League due to an injury-stricken forward line at United.

In Pereira's absence, as well as a long-term injury to Marouane Fellaini, McTominay has jumped up in the pecking order and has largely done well. The jury is still out on whether he can fulfill the potential in the way his manager and teammates have predicted, but he should be happy with the start he has made.