Tim Kelly (35 disposals, two goals) won plenty of the football for the Eagles, while Oscar Allen kicked three goals from limited chances.
The Eagles, who were forced to make seven changes this past week due to injury, threw themselves into their work in the opening term and made the game as competitive as they could and for a half, it largely worked as they pressured the Demons and made them earn their goals.
But in the third term, the Demons repeatedly pushed the ball into their forward 50-metre arc and it soon turned into goals as McDonald kicked two goals, while Petracca, Kade Chandler and Viney all kicked majors.
West Australian native and Demons key forward Jacob van Rooyen also kicked a goal late in the third to push the margin past 10 goals.
Kysaiah Pickett looked better with every minute in his return from suspension, kicking two late goals.
Running defender Michael Hibberd looked his usual, hard-running self in the first three terms before being subbed out in favour of James Jordon for the final term. The Eagles did the same thing with Elliot Yeo in his return from injury, and he looked promising in patches with 12 disposals.
McDonald with a point to prove
Premiership winner Tom McDonald returned to the side in place of injured Ben Brown (back) and he played like he had a point to prove in the opening term as the Demons try to figure out where he fits in their best forward set-up.
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McDonald kicked two of the club’s first three goals and showed his vision and poise just before the siren when he won the ball on the wing and sent in a piercing kick for Bayley Fritsch (three goals) to mark, which led to him kicking a goal and pushing the lead to 17 points.
McDonald’s form and van Rooyen’s athleticism and energy will make for a selection conundrum once Brown is fit to return.
Kelly powering Eagles
Midfielder Tim Kelly willed himself into countless contests in the first half and won more than his fair share of the football. But even more impressive were his 19 possessions in the first half.
Kelly needs more assistance in the midfield as he remains a match-winner, when that assistance will be fit and on the park remains unclear.
MELBOURNE 5.1 8.4 14.9 19.12 (126)
WEST COAST 2.2 4.4 6.8 9.9 (63)
GOALS
Melbourne: McDonald 4, Fritsch 3, Petracca 3, van Rooyen 2, Spargo 2, Pickett 2, Neal-Bullen, Viney, Chandler.
West Coast: Allen 3, Kelly 2, Hunt, West, Long, Petrevski-Seton.
BEST
Melbourne: Grundy, Oliver, McDonald, Petracca, Viney, Fritsch.
West Coast: Kelly, Allen, Barrass, Gaff, Hunt.
UMPIRES
Johanson, Stevic, Bryce, Tee
CROWD
42,458 at Optus Stadium
VOTES
Brodie Grundy (Melbourne) 8
Clayton Oliver (Melbourne) 8
Tim Kelly (West Coast) 7
Tom McDonald (Melbourne) 7
Christian Petracca (Melbourne) 6
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