Greenwood replaced Nemanja Matic after 81 minutes at the Emirates Stadium and displayed his excellent potential throughout the closing stages, when the Reds were attempting to come from behind after conceding goals to Gunners duo Granit Xhaka and Pierre-Emerick Aubameyang.
17y 160d - Mason Greenwood is the second youngest ever player to debut for @ManUtd in the Premier League, after Angel Gomes in May 2017 (16y 263d v Crystal Palace). Bloom. #ARSMUN
During the post-match discussion on MUTV, former United striker and Academy graduate Webber was keen to explain what those minutes in a big Premier League match signify for Greenwood.