Blakey was born in
Melbourne. His father,
John Blakey, was a
Fitzroy player and dual premiership midfielder for
North Melbourne. He moved to
Brisbane with his family at two years of age, due to his father assistant coaching at
Brisbane Lions, before settling in
Sydney as a six-year-old when his father joined
Sydney Swans coaching panel. He grew up in
Sydney's Eastern Suburbs and attended
Waverley College. Blakey participated in the
Auskick program at East Sydney Bulldogs. In his final year of junior football, he scored 18 goals. Blakey had a choice of three possible clubs,
North Melbourne and the
Brisbane Lions through the
father-son rule, and the
Sydney Swans as a member of the
Swans' Development Academy. In early 2018, Blakey revealed his preference was to play for the Sydney Swans. He was recruited by the
Sydney Swans with the 10th draft pick in the
2018 AFL draft matching a bid from . Blakey received a
2019 AFL Rising Star nomination in round 14 of the
2019 AFL season, for his two goal effort against .{{Cite news|url=https://www.theage.com.au/sport/afl/sydney-rookie-blakey-awarded-rising-star-nomination-20190624-p520us.html|title=Sydney rookie Blakey awarded Rising Star nomination ==AFL career==