He then competed in the 2021 Radical Intercontinental Cup at the Algarve International Circuit in Portugal.

[1] Competing full-time in the 2022 season with Valour Racing, he won the championship.

[2] Later in the year, he contested the inaugural Radical Cup World Finals at the Spring Mountain Motorsports Ranch in Nevada, United States,[3] which he won overall.

[4] In 2023, he moved up to the SR3 category of the Radical Cup UK, alongside his British Endurance Championship commitments.

DeLeon won the 2023 Team HARD Scholarship,[7] enabling him to compete in the 2023 British Endurance Championship with Team HARD, driving an Audi S3 touring car alongside Maurice Henry.