Johannes Martinus " Jan" Siemerink (; born 14 April 1970) is a retired tennis player from the Netherlands. The former Dutch Davis Cup captain reached a career-high ATP rankings of 14.
Siemerink turned professional in 1989. Over the course of his career, he won four top-level singles titles (at Singapore in 1991, Nottingham in 1996, and at Rotterdam and Toulouse in 1998). He also won ten tour doubles titles, the most significant of which were the Miami Masters in 1993 and the Monte-Carlo Masters in 1996.
Siemerink's best performance at a Grand Slam event came at Wimbledon in 1998, where he reached the quarterfinals by defeating Ctislav Doseděl, David Prinosil, Jonas Björkman and Magnus Larsson, before being knocked-out by Goran Ivanišević in three tie-breaks. Siemerink is also known for winning a fourth set tie-break against compatriot Richard Krajicek from 6–0 down in the 1994 US Open, though Krajicek eventually won the match.
Siemerink played for the Netherlands in the Davis Cup between 1991 and 2001, compiling a 17–10 record. He helped the Netherlands reach the World Group semi-finals in 2001.
Siemerink's career-high rankings were world No. 14 in singles (in 1998) and world No. 16 in doubles (in 1996). His career prize-money totaled $4,347,693.
After his playing career Siemerink was captain of the Dutch Davis Cup team from 2006 until 2016.
| {class=wikitable style=font-size:97% !Legend |
| Grand Slam Tournaments (0–0) |
| ATP World Tour Finals (0–0) |
| ATP Masters 1000 Series (0–0) |
| ATP 500 Series (0–2) |
| ATP 250 Series (4–6) |
| Hard (2–4) |
| Clay (0–1) |
| Grass (1–0) |
| Carpet (1–3) |
| Outdoors (2–3) |
| Indoors (2–5) |
| Win | 1–0 | Singapore, Singapore | World Series | Hard | Gilad Bloom | 6–4, 6–3 | |
| Loss | 1–1 | Vienna Open, Austria | World Series | Carpet | Michael Stich | 4–6, 4–6, 4–6 | |
| Loss | 1–2 | Marseille, France | World Series | Carpet | Marc Rosset | 2–6, 6–7(1–7) | |
| Loss | 1–3 | Amsterdam, Netherlands | World Series | Clay | Marcelo Ríos | 4–6, 5–7, 4–6 | |
| Loss | 1–4 | Long Island, United States | International Series | Hard | Yevgeny Kafelnikov | 6–7(0–7), 2–6 | |
| Loss | 1–5 | Swiss Indoors, Switzerland | World Series | Hard | Jim Courier | 7–6(7–2), 6–7(5–7), 7–5, 2–6, 5–7 | |
| Win | 2–5 | Nottingham Open, United Kingdom | World Series | Grass | Sandon Stolle | 6–3, 7–6(7–0) | |
| Loss | 2–6 | New Haven, United States | Championship Series | Hard | Alex O'Brien | 6–7(6–8), 4–6 | |
| Loss | 2–7 | Vienna Open, Austria | Championship Series | Carpet | Boris Becker | 4–6, 7–6(9–7), 2–6, 3–6 | |
| Loss | 2–8 | Stockholm Open, Sweden | International Series | Hard | Jonas Björkman | 6–3, 6–7(2–7), 2–6, 4–6 | |
| Win | 3–8 | Rotterdam Open, Netherlands | World Series | Carpet | Thomas Johansson | 7–6(7–2), 6–2 | |
| Win | 4–8 | Toulouse, France | World Series | Hard | Greg Rusedski | 6–4, 6–4 |
| {class=wikitable style=font-size:97% !Legend |
| Grand Slam Tournaments (0–0) |
| ATP World Tour Finals (0–0) |
| ATP Masters 1000 Series (2–0) |
| ATP 500 Series (0–1) |
| ATP 250 Series (8–6) |
| Hard (2–3) |
| Clay (4–1) |
| Grass (2–1) |
| Carpet (2–2) |
| Outdoors (8–4) |
| Indoors (2–3) |
| Loss | 0–1 | Rosmalen, Netherlands | World Series | Grass | Richard Krajicek | Hendrik Jan Davids Paul Haarhuis | 3–6, 6–7 | |
| Win | 1–1 | Hilversum, Netherlands | World Series | Clay | Richard Krajicek | Francisco Clavet Magnus Gustafsson | 7–5, 6–4 | |
| Loss | 1–2 | Berlin, Germany | World Series | Carpet | Daniel Vacek | Petr Korda Karel Nováček | 6–3, 5–7, 5–7 | |
| Win | 2–2 | Miami, United States | Masters Series | Hard | Richard Krajicek | Patrick McEnroe Jonathan Stark | 6–7, 6–4, 7–6 | |
| Win | 3–2 | Marseille, France | World Series | Carpet | Daniel Vacek | Martin Damm Yevgeny Kafelnikov | 6–7, 6–4, 6–1 | |
| Win | 4–2 | Hilversum, Netherlands | World Series | Clay | Daniel Orsanic | David Adams Andrei Olhovskiy | 6–4, 6–2 | |
| Loss | 4–3 | Doha, Qatar | World Series | Hard | Andrei Olhovskiy | Stefan Edberg Magnus Larsson | 6–7, 2–6 | |
| Win | 5–3 | Rosmalen, Netherlands | World Series | Grass | Richard Krajicek | Hendrik Jan Davids Andrei Olhovskiy | 7–5, 6–3 | |
| Loss | 5–4 | Stuttgart Open, Germany | Championship Series | Clay | Ellis Ferreira | Tomás Carbonell Francisco Roig | 6–3, 3–6, 3–6 | |
| Win | 6–4 | Vienna Open, Austria | World Series | Carpet | Ellis Ferreira | Todd Woodbridge Mark Woodforde | 6–4, 7–5 | |
| Win | 7–4 | Sydney, Australia | World Series | Hard | Ellis Ferreira | Patrick McEnroe Sandon Stolle | 5–7, 6–4, 6–1 | |
| Win | 8–4 | Monte Carlo, Monaco | Masters Series | Clay | Ellis Ferreira | Jonas Björkman Nicklas Kulti | 2–6, 6–3, 6–2 | |
| Loss | 8–5 | Sydney, Australia | World Series | Hard | Paul Haarhuis | Luis Lobo Javier Sánchez | 4–6, 7–6, 3–6 | |
| Loss | 8–6 | Copenhagen Open, Denmark | International Series | Carpet | Brett Steven | Tom Kempers Menno Oosting | 4–6, 6–7 | |
| Win | 9–6 | 's-Hertogenbosch, Netherlands | International Series | Grass | Guillaume Raoux | Joshua Eagle Andrew Florent | 7–6, 6–2 | |
| Loss | 9–7 | Toulouse, France | World Series | Hard | Paul Haarhuis | Olivier Delaître Fabrice Santoro | 2–6, 4–6 | |
| Cancelled | 9–7 | 's-Hertogenbosch, Netherlands | International Series | Grass | Leander Paes | Ellis Ferreira David Rikl | cancelled (rain) | |
| Win | 10–7 | Orlando, United States | International Series | Clay | Leander Paes | Justin Gimelstob Sébastien Lareau | 6–3, 6–4 |
| {class=wikitable style=font-size:97% !Legend |
| ATP Challenger (3–2) |
| ITF Futures (0–0) |
| Hard (0–2) |
| Clay (0–0) |
| Grass (0–0) |
| Carpet (3–0) |
| Win | 1–0 | Telford, United Kingdom | Challenger | Carpet | Martin Laurendeau | 6–3, 6–4 | |
| Win | 2–0 | Aachen, Germany | Challenger | Carpet | David Prinosil | 5–7, 7–6, 6–4 | |
| Loss | 2–1 | Segovia, Spain | Challenger | Hard | Sergi Bruguera | 7–5, 3–6, 0–1 ret. | |
| Loss | 2–2 | Grenoble, France | Challenger | Hard | Antony Dupuis | 6–7(10–12), 6–7(11–13) | |
| Win | 3–2 | Charleroi, Belgium | Challenger | Carpet | Paradorn Srichaphan | 7–6(7–2), 7–6(10–8) |
| {class=wikitable style=font-size:97% !Legend |
| ATP Challenger (6–1) |
| ITF Futures (0–0) |
| Hard (1–0) |
| Clay (2–0) |
| Grass (0–0) |
| Carpet (3–1) |
| Win | 1–0 | Tampere Open, Finland | Challenger | Clay | Mark Koevermans | Massimo Cierro Tobias Svantesson | 6–1, 6–2 | |
| Win | 2–0 | The Hague, Netherlands | Challenger | Carpet | Mark Koevermans | Alexander Mronz Andrei Olhovskiy | 6–3, 7–5 | |
| Loss | 2–1 | Telford, United Kingdom | Challenger | Carpet | Peter Nyborg | Martin Laurendeau Leonardo Lavalle | 6–7, 3–6 | |
| Win | 3–1 | Réunion Island, Réunion | Challenger | Hard | Clinton Ferreira | Álex Calatrava Jérôme Golmard | 6–2, 6–3 | |
| Win | 4–1 | Heilbronn, Germany | Challenger | Carpet | John Van Lottum | Magnus Larsson Fredrik Lovén | 7–5, 7–6(8–6) | |
| Win | 5–1 | Paget, Bermuda | Challenger | Clay | Leander Paes | Jeff Coetzee Brent Haygarth | 6–3, 6–2 | |
| Win | 6–1 | Aachen, Germany | Challenger | Carpet | Sander Groen | Michael Kohlmann Franz Stauder | 6–7(2–7), 7–6(9–7), 6–3 |
| Grand Slam tournaments | ||||||||||||||||||||||
| Australian Open | A | 4R | 2R | 3R | 2R | 2R | 3R | 1R | 2R | 1R | 1R | 2R | A !0 / 11 !12–11 ! | |||||||||
| French Open | A | 1R | 1R | 1R | A | 1R | 2R | 3R | 1R | 1R | Q1 | 1R | Q3 !0 / 9 !3–9 ! | |||||||||
| Wimbledon | Q1 | 1R | 1R | 1R | A | 3R | 1R | 1R | QF | 1R | 1R | 1R | A !0 / 10 !6–10 ! | |||||||||
| US Open | A | 3R | 3R | 2R | 1R | 1R | 3R | 1R | 4R | 1R | 1R | 2R | Q1 !0 / 11 !11–11 ! | |||||||||
| National Representation | ||||||||||||||||||||||
| Summer Olympic Games | NH | 1R | Not Held | 1R | Not Held | A | NH !0 / 2 !0–2 ! | |||||||||||||||
| ATP Masters Series | ||||||||||||||||||||||
| Indian Wells | A | A | A | A | A | A | A | A | A | 3R | A | A | A !0 / 1 !2–1 ! | |||||||||
| Miami | A | 3R | 1R | 1R | 4R | 4R | 2R | 2R | 3R | 3R | Q2 | 2R | A !0 / 10 !11–10 ! | |||||||||
| Monte Carlo | A | A | 1R | 1R | A | 2R | 2R | 2R | 1R | 1R | Q1 | Q1 | A !0 / 7 !3–7 ! | |||||||||
| Hamburg | A | A | 1R | A | A | 2R | 1R | 1R | 1R | A | A | A | A !0 / 5 !1–5 ! | |||||||||
| Rome | A | 1R | 1R | 3R | 2R | 2R | 1R | 2R | 1R | 2R | A | A | A !0 / 9 !6–9 ! | |||||||||
| Canada | A | A | A | A | A | A | A | 2R | 1R | 2R | A | A | A !0 / 3 !2–3 ! | |||||||||
| Cincinnati Open | A | A | 1R | 3R | Q1 | 3R | 1R | QF | 3R | 2R | A | A | A !0 / 7 !10–7 ! | |||||||||
| Paris Masters | A | 1R | Q2 | A | A | 3R | 1R | 2R | 2R | A | A | A | A !0 / 5 !2–5 ! | |||||||||
| Grand Slam tournaments | ||||||||||||||||||||||
| Australian Open | A | 1R | SF | 3R | 2R | 1R | 1R | 1R | 1R | 2R | 2R | 1R !0 / 11 !9–11 ! | ||||||||||
| French Open | A | 2R | 1R | 1R | A | 3R | 1R | 3R | 1R | 3R | 1R | 1R !0 / 10 !7–10 ! | ||||||||||
| Wimbledon | 1R | 1R | 1R | 1R | A | QF | SF | 1R | 2R | A | 2R | 2R !0 / 10 !10–10 ! | ||||||||||
| US Open | A | 2R | 1R | 1R | 1R | 1R | 2R | 1R | 1R | 1R | 1R | 1R !0 / 11 !2–11 ! | ||||||||||
| ATP Masters Series | ||||||||||||||||||||||
| Indian Wells | A | A | A | A | A | A | A | A | A | Q1 | A | A !0 / 0 !0–0 ! | ||||||||||
| Miami | A | A | 3R | W | SF | 3R | 3R | 1R | A | 1R | A | Q1 !1 / 7 !15–6 ! | ||||||||||
| Monte Carlo | A | A | 2R | QF | A | 2R | W | 1R | A | A | A | Q2 !1 / 5 !8–4 ! | ||||||||||
| Hamburg | A | A | 1R | A | A | 2R | 1R | 1R | A | A | A | A !0 / 4 !1–4 ! | ||||||||||
| Rome | A | 2R | A | 1R | 2R | SF | SF | 1R | A | Q1 | A | A !0 / 6 !8–6 ! | ||||||||||
| Canada | A | A | A | A | A | A | A | 1R | 2R | 1R | A | A !0 / 3 !1–3 ! | ||||||||||
| Cincinnati Open | A | A | Q1 | QF | 1R | QF | SF | 2R | 1R | A | A | A !0 / 6 !8–6 ! | ||||||||||
| Paris Masters | A | 1R | A | A | A | 1R | 2R | Q2 | A | A | A | A !0 / 3 !0–3 ! | ||||||||||
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