McTominay, who got his first taste of the competition as a late substitute in the reverse fixture last month, was named among the starters at Old Trafford on Tuesday night and showed composure beyond his year to complement an impressive set of technical attributes.
Matic played alongside the 20-year-old in central midfield, and not only is he convinced that McTominay will become a 'great player' in time, the Serbian has also vowed to do all he can in training to help his young team-mate fulfil his potential.
"I think Scott is going to be a great player and already is a great player," Matic enthused to MUTV.
"He's very young, very talented and physically strong. I'm sure he is the future of Manchester United and I enjoy playing with him because he also works really hard and is very confident.
"I'm going to help him in training because I think with his potential he's going to be a big star for Manchester United."
Despite Jose Mourinho's longstanding reputation for overlooking young players, McTominay was handed a United debut in the closing stages of last season when he appeared from the bench in a Premier League game against Arsenal - Axel Tuanzebe also played that game.
He later played 90 minutes on the final day of the Premier League season against Crystal Palace as part of a very young side and has continued to be involved with the first-team in 2017/18 as a result of injuries to Paul Pogba, Michael Carrick and Marouane Fellaini.
McTominay recently signed a new long-term contract with United that promises to keep him at Old Trafford until 2021, with the option of a further 12 months as well.