William Kjellberg
2025
| J60 DUBAI | [2] | (continue) |
| J60 LIVERPOOL | [1] | 1R |
| J60 TAMPERE | [1] | Semi |
| J100 PALERMO | [2] | 1R |
| J60 KAARINA | [1] | Win |
| J60 VESKA | [5] | Quarter |
| J60 BLUDENZ | [6] | Win |
| J60 TALLINN | [6] | Win |
| J60 HOLTE | [3] | 2R |
| J60 GDANSK | [5] | Quarter |
| J60 JONKOPING | [4] | Quarter |
| J30 BELLINZONA | [2] | Win |
| J60 ADAZI | [8] | 1R |
| J60 GREMDA | 1R | |
| J100 BROMMA | Quarter |
2024
| J30 VILNIUS | [3] | Quarter |
| J30 HANKO-2 | [2] | 2R |
| J30 VADUZ | [1] | Semi |
| J30 HANKO | [3] | Final |
| J30 HASSELT-2 | [6] | 2R |
| J30 SIAULIAI | 1R | |
| J30 SARAJEVO | [5] | 2R |
| J30 EDINBURGH | [5] | 2R |
| J60 BASTAD | [16] | 2R |
| J60 JONKOPING | 1R | |
| J30 SUNDSVALL | [7] | Final |
| J60 GJOVIK | 2R | |
| J60 VIERUMAKI | 2R | |
| J30 MURSKASOBOTA | 2R |
2023
Nation
SWE
Generation
Born in 2009 (15-16 years old)
World Ranking
Junior World Ranking 359th
Year-end Junior World Ranking
- Year-end 2024 992th
- Year-end 2023 3035th
Rival
Lorenzo Elia (2-0)
Lucas Christmas Moeller (2-0)
Hitoshi Shirabe (2-0)
Julian Theler (1-1)
Aleksandrs Sotikovs (1-1)
Match Details
2025 J60 DUBAI
| W | 1R | Daniil Tkachenko | 6-4 6-1 |
| W | 2R | Lazar Mladenovic | 7-6 6-3 |
| W | QF | Issah Ali | 6-4 6-0 |
2025 J60 LIVERPOOL
| L | 1R | Charlie Ruffell | 1-6 4-6 |
2025 J60 TAMPERE
| W | 1R | Kaius Ketola | 6-1 6-1 |
| W | 2R | Hitoshi Shirabe | 6-2 6-3 |
| W | QF | Aatu Niemelae | 6-2 6-1 |
| L | SF | Ken Ink | 3-6 4-6 |
2025 J100 PALERMO
| L | 1R | Francesco Pansecchi | 3-6 6-1 3-6 |
2025 J60 KAARINA
| W | 1R | Oliver Kiljunen | 6-1 6-3 |
| W | 2R | Felix Triquart | 6-0 6-3 |
| W | QF | Alex Tuomolin | 6-0 6-1 |
| W | SF | William Kaltenecker | 6-2 6-0 |
| W | F | Zac Naughton | 6-3 6-1 |
2025 J60 VESKA
| W | 2R | Josef Svoboda | 6-3 6-1 |
| W | 3R | Daniel Bernovskyi | 1-6 6-4 6-3 |
| L | QF | Tymon Litwic | 6-7 4-6 |
2025 J60 BLUDENZ
| W | 1R | Lorenzo Elia | 6-3 7-5 |
| W | 2R | Valentin Klaunzner | 6-1 2-6 6-1 |
| W | QF | Benjamin Freyholdt | 6-1 6-2 |
| W | SF | Niklas Maislinger | 7-5 6-1 |
| W | F | Dominik Dujka | 7-6 6-2 |
2025 J60 TALLINN
| W | 1R | Hitoshi Shirabe | 6-3 6-1 |
| W | 2R | Lucas Christmas Moeller | 6-3 6-4 |
| W | QF | Edwin Averjanov | 6-2 6-2 |
| W | SF | Mathias Skrlik | 6-1 6-0 |
| W | F | Aleksandrs Sotikovs | 6-3 6-3 |
2025 J60 HOLTE
| L | 2R | Christoffer Topp-Parving | 3-6 6-4 2-6 |
2025 J60 GDANSK
| W | 1R | Jan Skrzynski | 7-6 6-3 |
| W | 2R | Martin Fuks | 6-2 6-2 |
| L | QF | Alex Huszar | 3-6 1-6 |
2025 J60 JONKOPING
| W | 1R | Joel Henriksson | 7-6 4-6 6-3 |
| W | 2R | Lucas Christmas Moeller | 6-1 6-2 |
| L | QF | Jules Rimbaud | 6-3 4-6 3-6 |
2025 J30 BELLINZONA
| W | 1R | Noel Kim Bachmann | 6-0 6-2 |
| W | 2R | Lorenzo Rocco | 6-2 6-3 |
| W | QF | Julian Theler | 6-1 6-2 |
| W | SF | Lorenzo Elia | 6-3 6-2 |
| W | F | Neil Saxer | 6-3 6-7 7-6 |
2025 J60 ADAZI
| L | 1R | Hlib Kovalenko | 6-3 4-6 3-6 |
2025 J60 GREMDA
| L | 1R | Petar Ciangherotti | 6-2 4-6 4-6 |
2025 J100 BROMMA
| W | 1R | Arturs Zagars | 6-2 7-5 |
| W | 2R | Felix Alopaeus | 6-4 6-4 |
| L | QF | Victor Ryden | 0-6 4-6 |
2024 J30 VILNIUS
| W | 1R | Lorenzo Sverzut Corsini | 6-2 6-1 |
| W | 2R | Daniel Joita | 6-2 6-2 |
| L | QF | Samuel Mandelkorn | 4-6 2-6 |
2024 J30 HANKO-2
| W | 1R | Darsh Sachin Patel | 6-0 6-0 |
| L | 2R | Nikita Smirnov | 6-7 3-6 |
2024 J30 VADUZ
| W | 1R | Tiago Peterhans | 1-6 6-2 6-2 |
| W | 2R | Niccolo Crivelli | 6-4 6-2 |
| W | QF | Stepan Ziska | 7-6 7-5 |
| L | SF | Julian Theler | 3-6 4-6 |
2024 J30 HANKO
| W | 1R | Emil Torn | 6-3 6-1 |
| W | 2R | Aarne Koskinen | 6-3 6-3 |
| W | QF | Nicolo Romano | 6-0 6-1 |
| W | SF | Krystof Vymazal | 7-5 6-4 |
| L | F | Leo Stenlund | 1-6 6-7 |
2024 J30 HASSELT-2
| L | 2R | Dominik Vagner | 2-6 0-6 |
2024 J30 SIAULIAI
| L | 1R | Aleksandrs Sotikovs | 1-6 3-6 |
2024 J30 SARAJEVO
| W | 1R | Afan Nekovic | 6-4 6-3 |
| L | 2R | Todor Vukomanovic | 0-6 4-6 |
2024 J30 EDINBURGH
| W | 1R | Thomas Dixon | 6-2 6-1 |
| L | 2R | Brandon Ratanavong | 7-6 6-7 2-6 |
2024 J60 BASTAD
| L | 2R | Love Nyqvist | 2-6 6-4 0-6 |
2024 J60 JONKOPING
| L | 1R | Johan Oscar Lien | 1-6 5-7 |
2024 J30 SUNDSVALL
| W | 1R | Alessandro Fiocchi | 6-1 6-4 |
| W | 2R | Mick Ilnicki | 6-7 6-1 6-2 |
| W | QF | Tristan Thomas Engelschmidt | 6-0 6-0 |
| W | SF | Lukas Andersson | 7-5 6-4 |
| L | F | Tim Malmqvist | 6-3 2-6 0-6 |
2024 J60 GJOVIK
| W | 1R | Francis Alexander Lendvay Thoresen | 6-2 6-0 |
| L | 2R | Emanuel Ivanisevic | 4-6 4-6 |
2024 J60 VIERUMAKI
| W | 1R | Rasmus Stalmeister | 6-1 6-0 |
| L | 2R | Niels Mcdonald | 6-7 4-6 |
2024 J30 MURSKASOBOTA
| W | 1R | Benjamin Scharner | 7-6 6-0 |
| L | 2R | Daniel Klocurek | 4-6 6-4 1-6 |
2023 J30 STAVANGER
| W | 1R | Rasmus M Grindheim | 6-3 6-1 |
| W | 2R | Hartmut Fiedler | 6-1 6-0 |
| L | 3R | Sebastian Eie | 4-6 2-6 |
2023 J30 AIZKRAUKLE
| W | 1R | Mykyta Kolesnyk | 6-3 6-4 |
| L | 2R | Denis Maijorov | 2-6 1-6 |
2023 J30 BASTAD
| L | 1R | Hugo Petersson | 2-6 4-6 |
2023 J30 SUNDSVALL
| W | 1R | Jan Sadzik | 3-6 6-4 6-0 |
| L | 2R | Patrik Munkhammar | 2-6 4-6 |
Junior Tennis Database is a site that summarizes the results of ITF junior tennis tournaments.
Number of registered tournaments: 10086, Number of registered players: 6,349, Number of registered results: 362,939