Born in Sydney, Clarke studied at The King's School where he was coached by Nancy Atterton, a former sprinter and gold medalist in the 1954 British Empire and Commonwealth Games.

[1] Clarke started running at a young age, In December 2010, he set an Under-16 record with a time of 10.72 seconds in the 100m competing for NSW.

[2] He competed in the Australian Junior Athletics Championships in the 2012/13 season finishing 3rd overall behind Jarrod Geddes and Hugh Donovan with a time of 10.58 seconds.

[6] Clarke won the 2016 ACT Athletics Championships with a time of 10.15 seconds qualifying him for the 2016 Olympic Games.

[1] His run moved him from tenth to fifth on the Australian All Time list just behind Patrick Johnson (9.93), Matt Shirvington (10.03), Josh Ross (10.08) and Damien Marsh (10.13).