H2H data updated: 2026-09-02 00:00 UTC

Stefan Kozlov vs Donald Young H2H: 0-2

Donald Young holds a 2–0 lead over Stefan Kozlov in their ATP head-to-head. Across 2 main-draw meetings, Donald Young leads 1–0 on grass and 1–0 on hard courts. Most recently, Donald Young won the 2017 Indian Wells Open first round 7-5 7-6(5).

Want to explore more matchups? Advanced rivalry search lets you browse current and historical rivalries, unbeaten records, or every matchup for a player.

Stefan Kozlov
United States Age 28 Right-Handed 183 cm / 6'0"
H2H
0 – 2
2 main draw meetings
Donald Young
USA Age 37 Left-Handed 183 cm / 6'0"

H2H Match Log

PlayerScorePlayerMatch DataDateRoundTournamentCategorySurface
Donald Young #327 4-6 6-4 6-4 Stefan Kozlov #374 Match data Jan 7, 2021* Q2 Q Delray Beach Open ATP 250 Hard
Donald Young #60 7-5 7-6(5) Stefan Kozlov #116 Match data Mar 11, 2017* R128 Indian Wells Open Masters 1000 Hard
Donald Young #61 6-0 6-4 Stefan Kozlov #169 Match data Jul 15, 2016* R16 Newport ATP 250 Grass

1 qualifying meeting shown in the table; qualifying is excluded from the H2H score. Estimated match date where the exact historical date is unavailable. Arrows show an edition's recorded category and documented modern equivalent; unresolved editions keep their recorded category. Asterisked totals include editions mapped from documented historical predecessor categories. Mapping details.

Career Comparison

Player Current Peak Pts Elo W L Win % GS 1000 including documented historical predecessor categories Finals 500 including documented historical predecessor categories 250 including documented historical predecessor categories Titles
Stefan Kozlov #297 #103 558 1,673 9 26 25.7% 0 0 0 0 0 0
Donald Young #1,350 #38 1,039 1,932 125 188 39.9% 0 0 0 0 0 0

Career Progression by Age

Seasons are aligned by the age each player spent most of that calendar year. GS and Titles are cumulative career totals through that season.

Age Stefan Kozlov Donald Young
YrW-LWin %RankEloGSTitles YrW-LWin %RankEloGSTitles
15 2013 0–1 0.0% #1083 1,489 0 0 2005 0–7 0.0% #553 1,402 0 0
16 2014 0–1 0.0% #467 1,453 0 0 2006 0–3 0.0% #494 1,380 0 0
17 2015 0–2 0.0% #351 1,420 0 0 2007 3–3 50.0% #100 1,423 0 0
18 2016 3–2 60.0% #116 1,481 0 0 2008 8–20 28.6% #138 1,485 0 0
19 2017 2–9 18.2% #167 1,549 0 0 2009 0–4 0.0% #194 1,522 0 0
20 2018 0–1 0.0% #316 1,528 0 0 2010 3–6 33.3% #127 1,555 0 0
21 — — — — — — — 2011 19–17 52.8% #39 1,800 0 0
22 2020 0–1 0.0% #371 1,514 0 0 2012 5–24 17.2% #190 1,587 0 0
23 2021 0–1 0.0% #159 1,550 0 0 2013 2–3 40.0% #96 1,696 0 0
24 2022 4–8 33.3% #198 1,529 0 0 2014 18–21 46.2% #57 1,759 0 0
25 — — — — — — — 2015 21–22 48.8% #48 1,828 0 0
26 — — — — — — — 2016 18–21 46.2% #88 1,800 0 0
27 — — — — — — — 2017 25–22 53.2% #61 1,786 0 0
28 — — — — — — — 2018 3–12 20.0% #248 1,727 0 0
29 — — — — — — — 2019 0–2 0.0% #230 1,648 0 0
31 — — — — — — — 2021 0–1 0.0% #411 1,604 0 0

Surface Results by Age

Seasons are aligned by the age each player spent most of that calendar year. Results cover completed main-draw matches. Bold green marks the higher win percentage when both players have at least 5 matches on that surface at the aligned age.

Age Stefan Kozlov Donald Young
Yr HardClayGrass Yr HardClayGrass
W L M Win % W L M Win % W L M Win % W L M Win % W L M Win % W L M Win %
15 2013 — — — — — — — — 0 1 1 0.0% 2005 0 6 6 0.0% 0 1 1 0.0% — — — —
16 2014 0 1 1 0.0% — — — — — — — — 2006 0 3 3 0.0% — — — — — — — —
17 2015 0 2 2 0.0% — — — — — — — — 2007 3 3 6 50.0% — — — — — — — —
18 2016 — — — — — — — — 3 2 5 60.0% 2008 6 14 20 30.0% 1 3 4 25.0% 1 3 4 25.0%
19 2017 0 6 6 0.0% — — — — 2 3 5 40.0% 2009 0 4 4 0.0% — — — — — — — —
20 2018 — — — — 0 1 1 0.0% — — — — 2010 3 5 8 37.5% 0 1 1 0.0% — — — —
21 — — — — — — — — — — — — — 2011 16 13 29 55.2% — — — — 3 4 7 42.9%
22 2020 0 1 1 0.0% — — — — — — — — 2012 5 14 19 26.3% 0 6 6 0.0% 0 4 4 0.0%
23 2021 0 1 1 0.0% — — — — — — — — 2013 2 3 5 40.0% — — — — — — — —
24 2022 4 6 10 40.0% — — — — 0 2 2 0.0% 2014 13 16 29 44.8% 4 2 6 66.7% 1 3 4 25.0%
25 — — — — — — — — — — — — — 2015 21 15 36 58.3% 0 4 4 0.0% 0 3 3 0.0%
26 — — — — — — — — — — — — — 2016 11 15 26 42.3% 2 3 5 40.0% 5 3 8 62.5%
27 — — — — — — — — — — — — — 2017 20 15 35 57.1% 0 4 4 0.0% 5 3 8 62.5%
28 — — — — — — — — — — — — — 2018 3 10 13 23.1% 0 1 1 0.0% 0 1 1 0.0%
29 — — — — — — — — — — — — — 2019 0 2 2 0.0% — — — — — — — —
31 — — — — — — — — — — — — — 2021 0 1 1 0.0% — — — — — — — —
Career — 4 17 21 19.0% 0 1 1 0.0% 5 8 13 38.5% — 103 139 242 42.6% 7 25 32 21.9% 15 24 39 38.5%

Performance Progression by Age

Seasons are aligned by the age each player spent most of that calendar year. Detailed serve and return statistics available for 35/35 of Stefan Kozlov's and 310/313 of Donald Young's main draw matches. Sample is shown as matches with detailed serve and return statistics / total main draw matches. Bold green marks the stronger value when both stat samples contain at least 5 matches; lower is better for DFs/M.

Age Stefan Kozlov Donald Young
Yr Sample Aces/M DFs/M 1st Sv% 1st Pts% 2nd Pts% BP Saved% BP Conv% Svc Pts% Ret Pts% Yr Sample Aces/M DFs/M 1st Sv% 1st Pts% 2nd Pts% BP Saved% BP Conv% Svc Pts% Ret Pts%
15 2013 1/1 4.0 3.0 43.5% 74.5% 42.6% 62.5% 44.4% 56.5% 36.0% 2005 7/7 2.0 2.6 61.8% 55.4% 43.7% 41.0% 38.9% 50.9% 32.9%
16 2014 1/1 2.0 4.0 56.4% 61.3% 50.0% 63.6% 16.7% 56.4% 35.5% 2006 3/3 1.3 4.3 54.6% 47.1% 35.8% 15.7% 4.2% 41.9% 32.0%
17 2015 2/2 0.5 3.0 44.3% 48.1% 35.6% 27.8% 67.5% 41.3% 42.2% 2007 5/6 5.2 4.4 56.0% 75.2% 48.1% 63.4% 33.9% 63.1% 37.1%
18 2016 5/5 4.2 4.8 55.8% 67.8% 41.9% 67.2% 40.4% 56.9% 38.4% 2008 28/28 3.1 3.4 59.1% 66.0% 48.4% 61.2% 38.5% 58.9% 34.4%
19 2017 11/11 3.6 4.1 58.0% 65.2% 44.1% 53.2% 35.0% 56.5% 32.9% 2009 4/4 3.5 3.3 54.8% 66.6% 47.1% 54.6% 38.1% 56.1% 31.9%
20 2018 1/1 2.0 5.0 50.9% 65.5% 35.7% 20.0% 50.0% 50.9% 28.0% 2010 9/9 3.7 4.0 59.6% 67.5% 46.6% 53.3% 56.3% 59.1% 36.1%
21 — —/— — — — — — — — — — 2011 36/36 2.8 3.4 63.9% 67.3% 52.8% 54.0% 44.8% 61.9% 38.8%
22 2020 1/1 1.0 5.0 68.5% 54.1% 57.1% 36.4% 50.0% 55.1% 31.7% 2012 28/29 2.1 4.1 60.4% 63.8% 41.9% 52.3% 35.2% 54.9% 37.0%
23 2021 1/1 1.0 1.0 76.4% 54.8% 61.5% 42.9% 25.0% 56.4% 32.7% 2013 5/5 2.6 4.4 64.6% 62.3% 53.6% 60.7% 48.4% 57.6% 48.2%
24 2022 12/12 1.6 4.8 72.4% 60.0% 43.6% 59.6% 35.7% 55.2% 36.0% 2014 39/39 3.1 3.7 62.4% 69.1% 50.6% 52.6% 38.9% 62.2% 38.0%
25 — —/— — — — — — — — — — 2015 43/43 3.6 4.5 55.4% 69.5% 50.3% 49.7% 38.9% 61.1% 36.9%
26 — —/— — — — — — — — — — 2016 39/39 3.6 3.7 57.6% 70.7% 51.0% 60.9% 40.9% 62.7% 37.1%
27 — —/— — — — — — — — — — 2017 46/47 4.2 4.0 60.9% 69.1% 50.0% 58.3% 45.0% 61.5% 33.4%
28 — —/— — — — — — — — — — 2018 15/15 2.7 4.4 60.3% 63.1% 48.9% 51.9% 43.4% 57.0% 33.3%
29 — —/— — — — — — — — — — 2019 2/2 1.0 2.5 59.3% 54.4% 44.2% 50.0% 17.1% 50.5% 37.2%
31 — —/— — — — — — — — — — 2021 1/1 4.0 6.0 58.9% 65.1% 36.7% 50.0% 50.0% 53.4% 29.4%
Career — 35/35 2.6 4.3 62.0% 62.4% 43.9% 54.8% 38.2% 55.1% 35.3% — 310/313 3.2 3.9 59.8% 67.4% 49.2% 54.7% 40.7% 60.0% 36.3%

Advanced Statistics Comparison by Age

Seasons are aligned by the age each player spent most of that calendar year. Metrics are precomputed from eligible main-draw results; point-stat values use the available detailed sample. Bold green marks the stronger value when both underlying samples are sufficient. Lower is better for Schedule because a negative value means a tougher schedule. Career Schedule is normalized per 100 matches.

Age Stefan Kozlov Donald Young
Yr Elo P+ Serve+ Return+ PD TPW% Hard Elo Clay Elo Grass Elo Set Win % Set Margin Dec. Set Tiebreak Pressure+ Schedule Yr Elo P+ Serve+ Return+ PD TPW% Hard Elo Clay Elo Grass Elo Set Win % Set Margin Dec. Set Tiebreak Pressure+ Schedule
14 — — — — — — — — — — — — — — — — 2004 1483 94.3 — — — — — — — — — — — — —
15 2013 1490 100.2 -4.35 +1.56 0.828 46.1% — — — 33.3% -1.33 0–1 1–0 — +0.13 2005 1402 94.5 -5.39 -2.99 0.671 41.9% +21 — — 0.0% -3.27 — 0–2 — +0.58
16 2014 1454 100.0 +0.67 0.00 0.813 45.3% — — — 0.0% -3.00 — — — -0.04 2006 1381 91.8 -3.44 -2.20 0.550 36.6% +7 — — 12.5% -4.00 — — — +0.11
17 2015 1420 101.3 -5.76 -0.97 0.718 41.8% — — — 0.0% -3.50 — — — +0.21 2007 1424 114.0 -0.74 +1.71 1.007 49.9% +6 — — 43.8% -0.06 1–1 0–2 — +0.03
18 2016 1481 107.5 -3.43 +1.33 0.891 48.1% — — +119 54.5% +0.09 1–0 — — -0.03 2008 1486 119.6 -3.47 -1.98 0.836 47.1% +9 -17 +42 33.8% -1.07 3–4 (43%) 2–8 (20%) — +0.92
19 2017 1550 118.7 -5.47 -0.25 0.757 44.9% -74 — +123 21.7% -1.70 2–1 (67%) 0–3 (0%) — +0.21 2009 1522 111.1 -0.60 -1.54 0.727 44.6% +11 — — 18.2% -2.09 0–1 1–0 — -0.14
20 2018 1528 106.2 +0.19 -0.20 0.570 40.2% — — — 0.0% -3.50 — — — -0.08 2010 1556 118.9 -1.42 -0.33 0.883 48.4% +27 — — 34.8% -0.78 0–1 0–2 — -0.09
21 2019 1514 100.9 — — — — — — — — — — — — — 2011 1801 137.2 -0.51 +1.10 1.019 50.0% +33 — -239 49.4% -0.15 5–4 (56%) 9–7 (56%) — +2.05
22 2020 1514 104.1 -1.24 +2.90 0.705 43.9% — — — 33.3% -2.33 0–1 1–0 — -0.06 2012 1588 122.1 -6.32 +0.15 0.820 45.9% +58 -147 -95 27.8% -1.51 4–9 (31%) 5–8 (38%) — +0.45
23 2021 1550 110.6 +2.69 +0.42 0.749 44.9% — — — 0.0% -3.00 — — — +0.04 2013 1696 130.6 -1.46 +1.87 1.137 52.9% +51 — — 30.0% -0.20 — — — -0.08
24 2022 1530 118.4 -4.38 +0.86 0.803 45.9% +20 — — 32.3% -1.48 2–0 1–1 — -0.54 2014 1760 144.1 -1.19 +1.54 1.003 50.0% -2 -165 -294 46.0% -0.18 6–8 (43%) 8–7 (53%) — +0.24
25 2023 1458 91.9 — — — — — — — — — — — — — 2015 1829 152.7 -2.57 +1.65 0.948 49.2% +46 -252 -393 47.7% -0.19 8–5 (62%) 5–2 (71%) — -0.51
26 2024 1433 92.7 — — — — — — — — — — — — — 2016 1801 143.0 -1.36 +0.89 0.994 50.0% +6 -187 -184 44.7% -0.19 4–5 (44%) 5–7 (42%) — +0.47
27 2025 1436 101.4 — — — — — — — — — — — — — 2017 1786 149.2 -1.67 -1.82 0.865 48.1% +15 -212 -63 47.2% -0.47 8–5 (62%) 12–4 (75%) — -0.96
28 2026 1418 97.5 — — — — — — — — — — — — — 2018 1727 131.1 -4.14 -0.47 0.774 45.1% +69 — — 22.2% -1.86 2–2 (50%) 4–5 (44%) — -1.41
29 — — — — — — — — — — — — — — — — 2019 1649 106.1 -2.97 +1.63 0.752 43.2% — — — 0.0% -3.25 — — — -0.14
30 — — — — — — — — — — — — — — — — 2020 1629 99.3 — — — — — — — — — — — — —
31 — — — — — — — — — — — — — — — — 2021 1604 96.3 -1.00 +0.69 0.631 43.5% — — — 0.0% -2.50 — — — -0.13
32 — — — — — — — — — — — — — — — — 2022 1574 93.3 — — — — — — — — — — — — —
33 — — — — — — — — — — — — — — — — 2023 1533 95.3 — — — — — — — — — — — — —
Career — 1674 113.0 -4.10 +0.48 0.784 45.4% -15 — +121 28.4% -1.58 5–3 (63%) 3–4 (43%) 104.8 -0.46 — 1933 139.0 -2.33 +0.16 0.907 48.3% +26 -163 -164 39.9% -0.68 41–45 (48%) 51–54 (49%) 103.1 +0.45

Career Rivalries

Each player's five most-played main-draw opponents. The current matchup is highlighted when it appears in a player's top five.