Gauthier Onclin (born 26 February 2001) is a Belgian tennis player who plays mainly on the ATP Challenger Tour. He has a career high ranking of world No. 194 achieved on 18 September 2023.[3][4]
In May, he defeated the higher-ranked Elias Ymer at a Challenger event in Bordeaux in the first round.[6] At the 2023 French Open he defeated Nicholas David Ionel in straight sets in the first round of qualifying before losing to Argentine Thiago Agustin Tirante in three sets.[7] Onclin got his revenge over the Argentine in the qualifying at the 2023 Wimbledon Championships, winning in straight sets during his first ever grass-court summer, as his junior years coincided with the grass-court portion of the Tour cancellation due to the COVID-19 pandemic.[8]
In October, he received a wildcard in doubles for the European Open in Antwerp, alongside compatriot Michael Geerts.[9] At the same tournament, in the qualifying singles competition, he defeated higher-ranked American Maxime Cressy.[10]