Juniors

As a junior, Darcis compiled a singles win–loss record of 73–32, reaching as high as No. 8 in the junior world singles rankings in May 2002 (and No. 15 in doubles). He reached the semifinals at the 2002 Wimbledon Championships boys' singles event.

2007–2009

Darcis won his first ATP World Tour event at the Dutch Open in July 2007 and achieved his first top-100 ranking on 26 November 2007 after winning a Challenger event in Finland.

Darcis competed at the 2008 Australian Open and the French Open, losing in the first round in both. He and Olivier Rochus, however, reached the quarterfinals of the doubles tournament at the French Open. He reached the second round at the US Open. He won a second ATP event at Memphis in March, defeating Robin Söderling in the final.^[6] He reached the final of the Dutch Open again, but lost to Albert Montañés.^[7]

In 2009, Darcis played in three Grand Slam tournaments, the Australian Open, Wimbledon, and the US Open, reaching the second round only at Wimbledon. He also reached the quarterfinals at Queen's Club.

2010–present

Darcis qualified for the 2010 Qatar Open, retiring in his third-round match against Rafael Nadal. He failed to qualify for the Australian Open.

At the 2011 French Open, Darcis advanced to the main draw as a qualifier, and in the first round pulled off a shock victory over 22nd seed Michaël Llodra. Darcis followed this up by beating Philipp Petzschner, to advance into the third round, where he was defeated by Frenchman Gaël Monfils in straight sets.

Darcis made the quarterfinals in Vienna, beating Nikolay Davydenko on the way, but was defeated by Daniel Brands.

In 2012, Darcis made the final of the Dallas Challenger tournament but lost to Jesse Levine. At the Eastbourne International, he defeated Matthew Ebden,^[8] Marcos Baghdatis,^[9] and Marinko Matosevic^[10] to face Andy Roddick in the semifinals. Darcis retired a set down at 1–3 due to a back injury.^[11]

At the 2012 Summer Olympics, Darcis beat Tomáš Berdych in the first round.^[12]

In the first round at the 2013 Wimbledon Championships on 24 June, Darcis defeated fifth-seeded Rafael Nadal in straight sets.^[13] This made him the first player ever to defeat Nadal in the first round of any major tournament. Darcis was ranked 130 places lower than Nadal. At the time, he was the lowest-ranked player ever to beat Nadal in a Grand Slam tournament.^[14] It was announced prior to his second-round match that he had withdrawn due to a shoulder injury sustained in the Nadal match.^[15]

In the 2017 Australian Open, Darcis defeated Sam Groth and Diego Schwartzman both in four sets to reach the third round, tying his best Grand Slam result to date (in singles). He was taken out by Andreas Seppi despite winning the first set of the match.^[16]

In October 2019, Darcis confirmed he plans to retire after the 2020 Australian Open due to elbow pain since the 2019 Wimbledon Championships.^[17]

Singles: 3 (2 titles, 1 runner-up)

Result	W–L	Date	Tournament	Tier	Surface	Opponent	Score
Win	1–0	Jul 2007	Dutch Open, Netherlands	250 Series	Clay	Werner Eschauer	6–1, 7–6(7–1)
Win	2–0	Mar 2008	U.S. National Indoor Championships, United States	500 Series	Hard (i)	Robin Söderling	6–3, 7–6(7–5)
Loss	2–1	Jul 2008	Dutch Open, Netherlands	250 Series	Clay	Albert Montañés	6–1, 5–7, 3–6

Singles: 39 (19–20)

Result	W–L	Date	Tournament	Tier	Surface	Opponent	Score
Loss	0–1	Sep 2003	Great Britain F10, Glasgow	Futures	Hard (i)	Andy Murray	3–6, 6–3, 3–6
Win	1–1	Nov 2003	Czech Rep. F6, Hrotovice	Futures	Carpet	Jan Mašík	3–6, 6–2, 6–2
Loss	1–2	May 2004	Italy F5, Padova	Futures	Clay	José Antonio Sánchez de Luna	3–6, 7–6(8–6), 6–7(8–10)
Loss	1–3	Jul 2004	Germany F11, Trier	Futures	Clay	Éric Prodon	3–6, 3–6
Loss	1–4	Jan 2005	Germany F1, Nußloch	Futures	Carpet (i)	Robin Vik	2–6, 3–6
Win	2–4	Jan 2005	France F1, Deauville	Futures	Clay (i)	Olivier Vandewiele	6–2, 6–1
Win	3–4	Jan 2005	France F2, Feucherolles	Futures	Hard (i)	Jean-Michel Péquery	6–4, 7–6(7–1)
Win	4–4	Mar 2005	France F4, Lille	Futures	Hard (i)	Roman Valent	7–5, 6–3
Loss	4–5	Oct 2005	Kolding, Denmark	Challenger	Hard (i)	Dmitry Tursunov	3–6, 4–6
Loss	4–6	Nov 2005	Eckental, Germany	Challenger	Carpet (i)	Michael Berrer	3–6, 6–4, 4–6
Loss	4–7	Apr 2006	France F7, Angers	Futures	Clay (i)	Stéphane Bohli	6–7(4–7), 7–6(7–4), 3–6
Win	5–7	Apr 2007	France F6, Angers	Futures	Clay (i)	Xavier Pujo	3–6, 6–4, 6–4
Win	6–7	Apr 2007	Turkey F3, Belek	Futures	Clay	Dušan Karol	6–3, 6–3
Win	7–7	Nov 2007	Helsinki, Finland	Challenger	Hard (i)	Tobias Kamke	6–3, 1–6, 6–4
Loss	7–8	Jun 2009	Prostějov, Czech Republic	Challenger	Clay	Jan Hájek	2–6, 6–1, 4–6
Loss	7–9	Mar 2010	Barletta, Italy	Challenger	Clay	Pere Riba	3–6, 0–0 ret.
Win	8–9	Aug 2010	Cordenons, Italy	Challenger	Clay	Daniel Muñoz de la Nava	6–2, 6–4
Loss	8–10	Oct 2010	Mons, Belgium	Challenger	Hard (i)	Adrian Mannarino	5–7, 2–6
Win	9–10	Jul 2011	Scheveningen, Netherlands	Challenger	Clay	Marsel İlhan	6–3, 4–6, 6–2
Win	10–10	Aug 2011	Trani, Italy	Challenger	Clay	Leonardo Mayer	4–6, 6–3, 6–2
Loss	10–11	Feb 2012	Dallas, United States	Challenger	Hard (i)	Jesse Levine	4–6, 4–6
Loss	10–12	May 2013	Ostrava, Czech Republic	Challenger	Clay	Jiří Veselý	4–6, 4–6
Win	11–12	Aug 2013	Netherlands F5, Enschede	Futures	Clay	Thomas Schoorel	7–6(7–2), 6–1
Loss	11–13	Jun 2014	Belgium F1, Damme	Futures	Clay	Joris De Loore	5–7, 3–6
Loss	11–14	Jul 2014	Belgium F7, Middelkerke	Futures	Clay	Niels Desein	3–6, 6–3, 6–7(6–8)
Win	12–14	Aug 2014	Belgium F10, Eupen	Futures	Clay	Richard Becker	7–6(7–5), 6–1
Win	13–14	Sep 2014	Belgium F14, Arlon	Futures	Clay	Scott Griekspoor	6–2, 6–2
Loss	13–15	Oct 2014	Mons, Belgium	Challenger	Hard (i)	David Goffin	3–6, 3–6
Win	14–15	Oct 2014	Rennes, France	Challenger	Hard (i)	Nicolas Mahut	6–2, 6–4
Win	15–15	Jan 2015	Nouméa, New Caledonia	Challenger	Hard	Adrián Menéndez Maceiras	6–3, 6–2
Win	16–15	Jun 2016	Lyon, France	Challenger	Clay	Thiago Monteiro	3–6, 6–2, 6–0
Loss	16–16	Jun 2016	Blois, France	Challenger	Clay	Carlos Berlocq	2–6, 0–6
Loss	16–17	Aug 2016	Liberec, Czech Republic	Challenger	Clay	Arthur De Greef	6–7(4–7), 3–6
Win	17–17	Aug 2016	Trnava, Slovakia	Challenger	Clay	Jordi Samper Montaña	6–3, 6–4
Loss	17–18	Oct 2016	Budapest, Hungary	Challenger	Hard (i)	Marius Copil	4–6, 2–6
Win	18–18	Nov 2016	Eckental, Germany	Challenger	Carpet (i)	Alex de Minaur	6–4, 6–2
Win	19–18	May 2017	Bordeaux, France	Challenger	Clay	Rogério Dutra Silva	7–6(7–2), 4–6, 7–5
Loss	19–19	Feb 2019	Cherbourg, France	Challenger	Hard (i)	Ugo Humbert	7–6(8–6), 3–6, 3–6
Loss	19–20	Nov 2019	Eckental, Germany	Challenger	Hard (i)	Jiří Veselý	4–6, 6–4, 3–6

Doubles: 10 (6–4)

Result	W–L	Date	Tournament	Tier	Surface	Partner	Opponents	Score
Win	1–0	Nov 2003	Czech Rep. F5, Frýdlant nad Ostravicí	Futures	Hard	Bart de Gier	Flavio Cipolla Alessandro da Col	7–6(7–5), 6–7(4–7), 6–3
Loss	1–1	Jun 2004	France F8, Blois	Futures	Clay	Stefan Wauters	Brian Dabul Diego Hartfield	5–7, 4–6
Win	2–1	Jan 2005	France F1, Deauville	Futures	Clay (i)	Stefan Wauters	Steven Korteling Nick van der Meer	6–4, 6–4
Win	3–1	Jul 2005	Montauban, France	Challenger	Clay	Stefan Wauters	Gabriel Trujillo Soler Lovro Zovko	6–4, 6–7(5–7), 6–4
Loss	3–2	Jul 2005	Scheveningen, Netherlands	Challenger	Clay	Kristof Vliegen	Julien Benneteau Édouard Roger-Vasselin	7–5, 5–7, 6–7(5–7)
Win	4–2	Apr 2007	Turkey F2, Manavgat	Futures	Clay	Fred Hemmes	Brett Ross Arnar Sigurdsson	6–2, 6–4
Loss	4–3	Apr 2007	Turkey F3, Belek	Futures	Clay	Fred Hemmes	Dušan Karol Jeroen Masson	3–6, 6–7(1–7)
Loss	4–4	May 2007	San Remo, Italy	Challenger	Clay	Stefan Wauters	Sanchai Ratiwatana Sonchat Ratiwatana	6–7(3–7), 3–6
Win	5–4	Feb 2010	Tanger, Morocco	Challenger	Clay	Dominik Meffert	Uladzimir Ignatik Martin Kližan	5–7, 7–5, [10–7]
Win	6–4	May 2013	Ostrava, Czech Republic	Challenger	Clay	Olivier Rochus	Tomasz Bednarek Mateusz Kowalczyk	7–5, 7–5

Singles

Current through the 2019 Swiss Open Gstaad.

* Darcis withdrew before the second round match at the 2013 Wimbledon.

Doubles