Kay Stumper vs Thibault Poret | WTT Youth Star Contender Wladyslawowo | U19 | BS | SF

Rinderer/Stumper vs Ionescu/Movileanu | WTT Youth Star Contender Wladyslawowo | U19 | BD | Finals

Kay Stumper vs Alexis Lebrun | WTT Youth Star Contender Wladyslawowo | U19 | BS | Finals

Rinderer/Stumper vs Kubik/Kulczycki | WTT Youth Star Contender Wladyslawowo | U19 | BD | SF

Kay Stumper vs Tobias Rasmussen (TTBL Selected) I Saison 2021/22

Cedric Meissner vs Kay Stumper (TTBL Selected) I Saison 2021/22

Sidorenko-Grebnev, boys doubles. ITTF World Youth Championships 2021.

Stumper Kay vs Ionescu Ovidiu | WTT Contender Tunis | MS | R16

Wang Yang vs Stumper Kay | WTT Contender Tunis | MS | R32

Kay Stumper vs Alexandre Cassin (Selected) | Saison 2021/22

Kay Stumper vs Lubomir Jancarik (Selected) | Saison 2021/22

Mattias Falck vs Kay Stumper (Selected) | Saison 2021/22