Keenan first competed for Canada at the 2011 Pan American Junior Athletics Championships in Miramar, Florida, where he won the bronze medal in the hammer throw with a distance of 66.62 meters.[1] Keenan would later compete at the 2012 World Junior Championships finishing in 28th place overall.[2]
At the 2014 NACAC U23 Championships in Athletics in Kamloops, British Columbia, Keenan won the bronze medal with a throw of 68.35 meters.[3]
In 2018, Keenan competed at the 2018 Commonwealth Games in Gold Coast, Australia finishing fourth in the hammer throw event, and followed that with a bronze medal finish at the 2018 NACAC Championships in Toronto, Ontario with a throw of 72.72 metres.[4] Keenan narrowly missed out on qualifying for the 2020 Summer Olympics in Tokyo, Japan.[5]
In June 2022, Keenan set a new personal best of 77.54 meters, which met the World Championships standard.[6] Later that month, Keenan won his fifth consecutive National title.[7] Keenan was also named to compete at both the 2022 World Athletics Championships and 2022 Commonwealth Games.[8][9][10][11]