With Romanian partner Nicholas David Ionel, he captured the 2020 Australian Open – Boys' doubles title by defeating Mikołaj Lorens and Kārlis Ozoliņš 6–7(8–10), 7–5, [10–4] in the final.

[2] He also reached the boys' singles final at the 2020 French Open, losing to compatriot Dominic Stricker 2–6, 4–6.

Riedi reached five finals on the ITF Men's World Tennis Tour, winning three and losing two.

In October, he won his first singles title at the M15 Selva Gardena tournament on hard courts in Italy.

In November, he won the 2022 HPP Open Challenger in Helsinki as a qualifier defeating Dimitar Kuzmanov and Jelle Sels,[4] moving 80 positions up in the rankings, finishing the year in the top 200 at No.

[6] He made his Masters 1000 main draw debut in Indian Wells as a qualifier where he lost to Jack Draper.

[8] In January, he won back-to-back Challenger titles in Oeiras, Portugal and in Ottignies-Louvain-la-Neuve, Belgium defeating in the latter, world No.