[3] Ritschard made his ATP Tour main-draw debut at the Suisse Open Gstaad in the doubles draw, partnering Alexander Sadecky.

[4] He drew fourth seeded Stefanos Tsitsipas who, despite his ranking, performed very poorly on grass, having lost in the first round of his two previous Wimbledon appearances.

[5][6][1] At the Swiss Open, he won his maiden ATP Tour match defeating eighth seed Joao Sousa as a wildcard.

[1][8] In October, he won his maiden Challenger title in Hamburg defeating Henri Laaksonen, after the fellow Swiss retired in the second set when Ritschard was 7–5, 6–5 up and had 40–30 on his service game, climbing 50 positions back to No.

[1][9] He qualified for the main draw of the 2023 BMW Open and defeated Jan-Lennard Struff but lost in the second round to Marcos Giron.