[13] He missed his first match of the year in round fifteen after he suffered from a bleeding lung as a result of a collision during the sixty-one point loss against Brisbane the previous week.

[21] He returned to the side for the eighty-three point loss against Collingwood in the annual Queen's Birthday clash in round eleven.

[39] The round sixteen match against Fremantle at TIO Stadium in a thirty-two point win saw McDonald record a career-high thirty-one disposals, ten marks, and six rebound-50s, which earned him the centre half-back position in AFL Media's team of the week.

[40] He played his 100th AFL match in the two-point win against Gold Coast at the Melbourne Cricket Ground in round nineteen.

[42] Following Max Gawn's early season hamstring injury, McDonald was used as a back-up ruckman to assist the undersized Cameron Pedersen.

Playing in this role, McDonald was awarded three Brownlow votes for amassing 26 disposals, twelve marks and a goal against the Essendon Bombers in round 5.

Following his success in the forward line during the previous season, it was believed that McDonald would continue in his newfound role while assisting in the ruck when required.

However, a niggling toe injury during the following pre-season kept McDonald sidelined for the opening five rounds of the 2018 AFL season, before he finally returned with two goals and 16 disposals in a 36-point win against Essendon.

During the 2018 Queen's Birthday match, McDonald kicked a career high six goals as Melbourne lost to Collingwood by 42 points.