He made his debut in the 25 point win against Hawthorn in the opening round of the 2017 season at the Melbourne Cricket Ground, recording 22 disposals.

[15] McGrath had another notable performance against Adelaide in round 21, where he kept star forward Eddie Betts goalless and held him to only seven disposals, his lowest output of the season.

He moved into Essendon's midfield full-time in 2020, and received the club's Adam Ramanauskas Most Courageous Player award in that year.

[21] For the 2021 season, the Essendon Football Club appointed McGrath a joint vice-captain alongside Michael Hurley and Zach Merrett.

[23] Early in the first term of the Bombers' round 12 match against Richmond on 5 June 2021, McGrath was substituted out with what proved to be a grade two posterior cruciate ligament injury, which was expected to put him out of action for eight to 12 weeks.