He won the gold medal in the men's high jump at the 2024 Summer Olympics.

In June 2019, Kerr equalled the national record with a jump of 2.30 m, winning the gold medal at the Oceania Athletics Championships in Townsville.

[2] He went on to compete at the Universiade in Naples, Italy, in July and then the World Athletics Championships in October in Doha, Qatar.

[3] Later the same year at the postponed 2020 Tokyo Olympics, he finished 10th in the men's high jump final with a clearance of 2.30 m. Kerr competed at the 2022 World Indoor Championships in Belgrade, Serbia, in March, where he surpassed the 39-year-old New Zealand indoor record of Roger Te Puni (of 2.16 m) with a bronze medal-winning jump of 2.31 m (tied with Gianmarco Tamberi).

He won the Oceania Athletics Championships in June that year, jumping 2.24 m. In August, he claimed the gold medal at the Commonwealth Games held in Birmingham with a jump of 2.25 m. In February 2023 at the Banskobystricka latka in Banská Bystrica, Slovakia, Kerr broke Tim Forsyth's Oceanian indoor record dating back to 1997 with a clearance of 2.34 m, a personal best.