Stefan Kozlov
2014
| Us Open Junior | [4] | Quarter |
| Wimbledon Junior | [6] | Final |
| Roland Garros Junior | [6] | Quarter |
| Australian Open Junior | [2] | Final |
2013
| Us Open Junior | [5] | 1R |
| Wimbledon Junior | Quarter | |
| Roland Garros Junior | 2R |
2012
Nation
USA
Age
27 years old (born in 1998)
World Ranking
ATP Ranking　433th
Match Details
2014 Us Open Junior
| W | 1R | Jan Zielinski | 6-2 6-3 |
| W | 2R | Rafael Matos | 7-6 6-4 |
| W | 3R | Seong Chan Hong | 6-3 2-6 6-3 |
| L | QF | Quentin Halys | WD |
2014 Wimbledon Junior
| W | 1R | Rafael Matos | 6-4 6-1 |
| W | 2R | Pedro Martinez | 6-0 6-2 |
| W | 3R | Naoki Nakagawa | 6-3 7-6 |
| W | QF | Hyeon Chung | 6-4 7-6 |
| W | SF | Johan Sebastien Tatlot | 6-3 7-6 |
| L | F | Noah Rubin | 4-6 6-4 3-6 |
2014 Roland Garros Junior
| W | 1R | Ryotaro Matsumura | 6-4 6-2 |
| W | 2R | Akira Santillan | 6-3 6-3 |
| W | 3R | Duckhee Lee | 7-6 6-1 |
| L | QF | Andrey Rublev | 5-7 6-3 4-6 |
2014 Australian Open Junior
| W | 1R | Blake Mott | WO |
| W | 2R | Simon Friis Soendergaard | 6-7 7-5 6-0 |
| W | 3R | Boris Pokotilov | 6-1 6-2 |
| W | QF | Andrey Rublev | 6-2 6-1 |
| W | SF | Quentin Halys | 2-6 7-6 6-3 |
| L | F | Alexander Zverev | 3-6 0-6 |
2013 Us Open Junior
| L | 1R | Lucas Miedler | 1-6 2-6 |
2013 Wimbledon Junior
| W | 1R | Joshua Sapwell | 6-3 6-3 |
| W | 2R | Lucas Gomez | 6-2 6-3 |
| W | 3R | Alexander Zverev | WO |
| L | QF | Kyle Edmund | 6-4 1-6 3-6 |
2013 Roland Garros Junior
| W | 1R | Matej Maruscak | 7-5 6-3 |
| L | 2R | Gianluigi Quinzi | 6-3 1-6 4-6 |
2012 Us Open Junior
| W | 1R | Stefano Napolitano | WO |
| W | 2R | Jordan Thompson | 6-3 6-7 6-3 |
| L | 3R | Wayne Montgomery | 2-6 3-6 |
2012 Wimbledon Junior
| W | 1R | Daniel Masur | 5-7 6-2 6-1 |
| L | 2R | Liam Broady | 7-6 0-6 4-6 |
Junior Tennis Database is a site that summarizes the results of ITF junior tennis tournaments.
Number of registered tournaments: 5774, Number of registered players: 3,011, Number of registered results: 222,093