2009

2009 was Žemlja's first year at the main draw on the ATP Tour. For the first time in his career he qualified for the main draw of Wimbledon where he lost in first round against Albert Montañés. He was the second Slovenian male player ever to play in the main draw of the Grand Slam tournament.

2010

For the first time in his career he qualified for the main draw of the Australian Open where he lost in first round against Benjamin Becker. He became the first ever Slovenian male player to play in the main draw of Australian Open. Žemlja qualified for the 2010 French Open and scored an upset over the No. 26 seed Juan Mónaco, in his first ever Grand Slam victory. He became the first Slovenian male player to win a single match in the Grand Slam tournament. He also became the first Slovenian male player to perform in three different Grand Slam tournaments on three different surfaces.

For the first time in his career he participated in the ATP World Tour 500 series tournament at 2010 Legg Mason Tennis Classic in Washington, D.C. where he lost the second round match against Andy Roddick. Together with Slovenia Davis Cup Team he won the 2010 Davis Cup Europe/Africa Zone Group II, ensuring Slovenia to advance to Europe/Africa Zone Group I.

2011

For the second consecutive year, he qualified for the main draw of Australian Open where he lost the first round match against Marcos Baghdatis in five sets. As a lucky loser, he also qualified for the 2011 Wimbledon Championships. He became the first Slovenian male player to win a single match in the main draw of Wimbledon, but lost his second round match against Gaël Monfils.

2012

He played at 2012 Qatar Open in Doha and lost in straight sets against Roger Federer in second round. He received a wild card to participate in the 2012 Wimbledon Championships,^[1] where he lost the second round match against Fernando Verdasco.

On 6 August 2012, he entered the top 100 of the ATP rankings. For the first time in his career he qualified for the main draw of the US Open. Beating Ricardo Mello and Cedrik-Marcel Stebe in first two rounds, he became the first Slovenian male player ever to reach the third round of the Grand Slam tournament. In the third round^[2] he lost against Janko Tipsarević. At 2012 Erste Bank Open tournament in Vienna, Austria, he reached his and Slovenian first male historic ATP Final,^[3] where he lost to Juan Martín del Potro. With that result he became the first Slovenian male tennis player to reach TOP 50 on ATP rankings.

2013

At 2013 Australian Open for the first time he directly entered Grand Slam tournament. He retired in the first round against Marcel Granollers. He also played his first men's doubles Grand Slam tournament.

He played against Roger Federer for the second time in his career in Rotterdam at 2013 ABN AMRO World Tennis Tournament of ATP 500 series. He lost in two sets in the first round. For the first time in his career he played in main draw of ATP 1000 Masters series at 2013 Miami Masters. As a first Slovenian he reached the third round and lost in two sets against Gilles Simon.

At 2013 French Open he reached second round where he lost in four sets against Kei Nishikori. In men's doubles partnering Aljaž Bedene they lost in two sets against Aisam-ul-Haq Qureshi/Jean-Julien Rojer in the second round. This is the first historic win in the first round of Grand Slam Slovenian men's doubles and first Slovene men's doubles performance in the French Open.

At 2013 Wimbledon Championships, he beat Michael Russell and 29th seed Grigor Dimitrov, becoming the first Slovene player in the third round of Wimbledon, where he lost in straight sets to Juan Martín del Potro. Partnering Aljaž Bedene in the first round of men's doubles they lost against Sanchai Ratiwatana and Sonchat Ratiwatana. This was the first Slovene men's doubles team at Wimbledon.

Singles: 1 (1 runner-up)

Result	W–L	Date	Tournament	Tier	Surface	Opponent	Score
Loss	0–1	Oct 2012	Vienna Open, Austria	250 Series	Hard (i)	Juan Martín del Potro	5–7, 3–6

Singles: 38 (17–21)

Result	W–L	Date	Tournament	Tier	Surface	Opponent	Score
Win	1–0	Jun 2004	Slovenia F2, Maribor	Futures	Clay	Carlos Berlocq	6–7(1–7), 6–3, 6–4
Loss	1–1	May 2005	Hungary F1, Budapest	Futures	Clay	Sebő Kiss	1–6, 2–6
Loss	1–2	May 2005	Bosnia & Herzegovina F1, Sarajevo	Futures	Clay	Ilija Bozoljac	4–6, 3–6
Win	2–2	Jun 2005	Slovenia F1, Kranj	Futures	Clay	Roman Vögeli	7–6(7–4), 6–3
Win	3–2	Jun 2005	Slovenia F2, Maribor	Futures	Clay	Vilim Visak	6–1, 7–5
Win	4–2	Jun 2005	Slovenia F3, Koper	Futures	Clay	Marco Pedrini	6–7(2–7), 6–4, 6–4
Loss	4–3	May 2006	Bosnia & Herzegovina F1, Sarajevo	Futures	Clay	Cesar Ferrer-Victoria	3–6, 6–7(6–8)
Win	5–3	Jun 2006	Slovenia F1, Portorož	Futures	Hard	Rasmus Nørby	6–1, 6–0
Loss	5–4	Sep 2006	Germany F15, Kempten	Futures	Clay	Tobias Summerer	4–6, 4–6
Loss	5–5	Oct 2006	Portugal F5, Ponta Delgada	Futures	Hard	Vjekoslav Skenderovic	4–6, 1–6
Loss	5–6	Feb 2007	Australia F1, Wollongong	Futures	Hard	Robert Smeets	5–7, 1–6
Win	6–6	Oct 2007	Germany F19, Leimen	Futures	Hard	Marcel Zimmermann	6–3, 7–5
Win	7–6	Mar 2008	Croatia F3, Poreč	Futures	Clay	Andrea Arnaboldi	7–6(7–4), 6–1
Win	8–6	Jun 2008	Slovenia F1, Krško	Futures	Clay	Marcel Zimmermann	4–6, 6–4, 6–1
Win	9–6	Jun 2008	Slovenia F3, Koper	Futures	Clay	Blaž Kavčič	2–6, 6–1, 6–2
Loss	9–7	Jun 2008	Recanati, Italy	Challenger	Hard	Horacio Zeballos	3–6, 4–6
Loss	9–8	Oct 2008	Croatia F10, Dubrovnik	Futures	Clay	Simone Vagnozzi	3–6, 4–6
Win	10–8	Nov 2008	Cancún, Mexico	Challenger	Clay	Martín Alund	6–2, 6–1
Loss	10–9	Feb 2009	Burnie, Australia	Challenger	Hard	Brydan Klein	3–6, 3–6
Loss	10–10	Sep 2009	Ljubljana, Slovenia	Challenger	Clay	Paolo Lorenzi	6–1, 6–7(4–7), 2–6
Loss	10–11	Nov 2009	Cancún, Mexico	Challenger	Clay	Nicolás Massú	3–6, 5–7
Loss	10–12	Jan 2010	Honolulu, United States	Challenger	Hard	Michael Russell	0–6, 3–6
Win	11–12	Feb 2011	Caloundra, Australia	Challenger	Hard	Bernard Tomic	7–6(7–4), 6–3
Loss	11–13	Jun 2011	Rijeka, Croatia	Challenger	Clay	Rui Machado	3–6, 0–6
Loss	11–14	Sep 2011	Ljubljana, Slovenia	Challenger	Clay	Paolo Lorenzi	2–6, 4–6
Loss	11–15	Nov 2011	Salzburg, Austria	Challenger	Hard	Benoît Paire	7–6(8–6), 4–6, 4–6
Win	12–15	Jun 2012	Nottingham, United Kingdom	Challenger	Grass	Karol Beck	7–6(7–3), 4–6, 6–4
Win	13–15	Jul 2012	Anning, China	Challenger	Clay	Aljaž Bedene	1–6, 7–5, 6–3
Win	14–15	Aug 2012	Beijing, China	Challenger	Hard	Wu Di	6–3, 6–0
Win	15–15	Jul 2013	Portorož, Slovenia	Challenger	Hard	Martin Fischer	6–4, 7–5
Loss	15–16	Feb 2015	Iran F4, Kish	Futures	Hard	Jules Marie	1–6, 4–6
Win	16–16	Mar 2015	Iran F5, Kish	Futures	Hard	Jules Marie	6–3, 6–3
Win	17–16	Apr 2015	China F4, Yuxi	Futures	Hard	Kim Cheong-Eui	7–6(7–4), 6–3
Loss	17–17	Aug 2015	Portorož, Slovenia	Challenger	Hard	Luca Vanni	3–6, 6–7(6–8)
Loss	17–18	Oct 2015	Las Vegas, United States	Challenger	Hard	Thiemo de Bakker	6–3, 3–6, 1–6
Loss	17–19	Apr 2016	Gwangju, South Korea	Challenger	Hard	Ričardas Berankis	3–6, 2–6
Loss	17–20	Apr 2016	Nanjing, China	Challenger	Clay	Ričardas Berankis	3–6, 4–6
Loss	17–21	Oct 2016	Traralgon, Australia	Challenger	Hard	Jordan Thompson	1–6, 2–6

Doubles: 14 (5–9)

Result	W–L	Date	Tournament	Tier	Surface	Partner	Opponents	Score
Loss	0–1	Jun 2004	Slovenia F2, Maribor	Futures	Clay	Rok Jarc	Germán Puentes-Alcaniz Antonio Baldellou-Esteva	2–6, 1–6
Loss	0–2	Aug 2004	Serbia & Montenegro F6, Niš	Futures	Clay	Rok Jarc	Nikola Ćirić Goran Tošić	0–1 ret.
Win	1–2	Nov 2004	Tunisia F5, Monastir	Futures	Hard	Bostjan Osabnik	Maciej Diłaj Piotr Dilaj	7–6(7–3), 6–3
Loss	1–3	Dec 2004	Tunisia F6, Mégrine	Futures	Hard	Bostjan Osabnik	Haythem Abid Malek Jaziri	6–7(3–7), 3–6
Loss	1–4	May 2005	Bosnia & Herzegovina F1, Sarajevo	Futures	Clay	Rok Jarc	Ilija Bozoljac Goran Tošić	3–6, 5–7
Win	2–4	Jun 2005	Slovenia F1, Kranj	Futures	Clay	Rok Jarc	Fabio Colangelo Alessandro Da Col	2–6, 7–6(8–6), 6–3
Win	3–4	Oct 2005	France F17, Saint-Dizier	Futures	Hard	Rok Jarc	Olivier Charroin Gary Lugassy	3–6, 7–6(7–4), 6–0
Loss	3–5	Oct 2006	Portugal F4, Albufeira	Futures	Hard	Blaž Kavčič	Vjekoslav Skenderovic Joško Topić	3–6, 0–6
Loss	3–6	Feb 2007	Australia F1, Wollongong	Futures	Hard	Xavier Audouy	Alberto Francis Troy Hahn	6–1, 2–6, 3–6
Loss	3–7	Apr 2007	Italy F11, Padova	Futures	Clay	Blaž Kavčič	Alejandro Fabbri Gabriel Trujillo Soler	6–7(5–7), 2–6
Loss	3–8	Jun 2010	Marburg, Germany	Challenger	Clay	Guillermo Olaso	Matthias Bachinger Denis Gremelmayr	4–6, 4–6
Win	4–8	Sep 2011	Ljubljana, Slovenia	Challenger	Clay	Aljaž Bedene	Roberto Bautista Agut Iván Navarro	6–3, 6–7(10–12), [12–10]
Loss	4–9	Jun 2012	Slovenia F1, Bled	Futures	Clay	Aljaž Bedene	Mislav Hizak Tristan-Samuel Weissborn	walkover
Win	5–9	Oct 2015	Sacramento, United States	Challenger	Hard	Blaž Kavčič	Daniel Brands Dustin Brown	6–1, 3–6, [10–3]

Singles

Singles performances (18–10)

Edition	Round	Date	Against	Surface	Opponent	Result	Outcome
2005 Europe/Africa Zone Group II	1R	3-04-2005	Ivory Coast	Hard (I)	Valentin Sanon	6–4, 6–4, 7–5	Win
	QF	7-15-2005	Latvia	Clay	Ernests Gulbis	5–7, 6–3, 6–1, 6–4	Win
	SF	9-25-2005	Portugal	Clay	Rui Machado	3–6, 3–6, 6–2, 4–6	Loss
2006 Europe/Africa Zone Group II	1R	4-07-2006	Algeria	Clay	Slimane Saoudi	7–5, 6–2	Win
		4-09-2006			Lamine Ouahab	3–6, 6–2, 6–4, 3–6, 4–6	Loss
	RPO	7-21-2006	Ireland	Grass	Kevin Sorensen	6–2, 7–5, 6–1	Win
		7-23-2006			Conor Niland	6–4, 6–2	Win
2007 Europe/Africa Zone Group II	1R	4-06-2007	Estonia	Carpet (I)	Jürgen Zopp	4–6, 6–4, 7–6(7–3), 6–3	Win
		4-08-2007			Mait Künnap	6–3, 6–2, 3–6, 6–7(2–7), 6–3	Win
	QF	7-22-2007	Morocco	Hard	Younes El Aynaoui	6–7(2–7), 2–6, 4–6	Loss
2008 Europe/Africa Zone Group II	RPO	7-18-2008	Tunisia	Clay	Malek Jaziri	3–6, 6–1, 4–6, 6–3, 6–4	Win
2009 Europe/Africa Zone Group II	1R	3-06-2009	Egypt	Carpet (I)	Sherif Sabry	7–5, 7–6(8–6), 6–2	Win
	QF	7-10-2009	Lithuania	Clay	Ričardas Berankis	6–1, 6–4, 6–3	Win
		7-12-2009			Dovydas Sakinis	6–4, 2–6, 6–1	Win
	SF	9-18-2009	Latvia	Carpet (I)	Andis Juška	6–1, 6–1, 6–4	Win
		9-20-2009			Ernests Gulbis	2–6, 6–3, 3–6, 5–7	Loss
2010 Europe/Africa Zone Group II	1R	3-05-2010	Norway	Hard (I)	Erling Tveit	6–2, 6–2, 7–6(7–2)	Win
	QF	7-09-2010	Bulgaria	Clay	Todor Enev	6–2, 6–1	Win
	SF	9-17-2010	Lithuania	Hard (I)	Ričardas Berankis	7–6(7–2), 6–4, 6–3	Win
		9-19-2010			Laurynas Grigelis	6–3, 7–6(7–4), 6–3	Win
2011 Europe/Africa Zone Group I	1R	3-04-2011	Finland	Clay (I)	Jarkko Nieminen	6–3, 3–6, 4–6, 3–6	Loss
		3-06-2011			Micke Kontinen	2–6, 6–3, 6–3, 6–3	Win
	2R	7-08-2011	Italy	Clay	Fabio Fognini	6–1, 4–6, 4–6, 4–6	Loss
		7-10-2011			Simone Bolelli	5–7, 3–6	Loss
2012 Europe/Africa Zone Group I	1R	2-10-2012	Denmark	Hard (I)	Kristian Pless	6–0, 6–1, 6–4	Win
	2R	4-06-2012	South Africa	Hard	Izak van der Merwe	1–6, 6–3, 3–6, 4–6	Loss
2013 Europe/Africa Zone Group I	1R	1-02-2013	Poland	Hard (I)	Łukasz Kubot	3–6, 2–6, 0–6	Loss
		3-02-2013			Jerzy Janowicz	6–7(4–7), 3–6, 3–6	Loss

Doubles performances (11–8)

Edition	Round	Date	Partnering	Against	Surface	Opponents	Result	Outcome
2005 Europe/Africa Zone Group II	1R	3-05-2005	Rok Jarc	Ivory Coast	Hard (I)	Claude N'Goran Valentin Sanon	6–2, 6–2 ret.	Win
	SF	9-24-2005		Portugal	Clay	Frederico Gil Leonardo Tavares	4–6, 2–6, 4–6	Loss
2006 Europe/Africa Zone Group II	1R	4-08-2006	Rok Jarc	Algeria	Clay	Lamine Ouahab Slimane Saoudi	2–6, 2–6, 4–6	Loss
	RPO	7-22-2006	Luka Gregorc	Ireland	Grass	James Cluskey Stephen Nugent	6–7(7–9), 6–3, 3–6, 6–3, 7–5	Win
2007 Europe/Africa Zone Group II	1R	4-07-2007	Luka Gregorc	Estonia	Clay (I)	Mait Künnap Jürgen Zopp	2–6, 6–3, 6–3, 6–7(5–7), 4–6	Loss
	QF	7-21-2007		Morocco	Hard	Reda El Amrani Younes El Aynaoui	6–7(2–7), 6–4, 6–4, 6–4	Win
2008 Europe/Africa Zone Group II	1R	4-12-2008	Marko Tkalec	Cyprus	Hard	Marcos Baghdatis Photos Kallias	6–7(4–7), 6–4, 2–6, 6–4, 1–6	Loss
	RPO	7-19-2008	Luka Gregorc	Tunisia	Clay	Haithem Abid Malek Jaziri	6–3, 5–7, 6–7(5–7), 5–7	Loss
2009 Europe/Africa Zone Group II	1R	3-07-2009	Marko Tkalec	Egypt	Carpet (I)	Karim Maamoun Sherif Sabry	6–2, 6–3, 6–3	Win
	QF	7-19-2009	Andrej Kračman	Lithuania	Clay	Ričardas Berankis Vadim Pinko	7–6(7–2), 6–3, 6–3	Win
	SF	9-19-2009	Luka Gregorc	Latvia	Carpet (I)	Ernests Gulbis Deniss Pavlovs	6–7(5–7), 6–4, 6–2, 2–6, 6–4	Win
2010 Europe/Africa Zone Group II	1R	3-06-2010	Luka Gregorc	Norway	Hard (I)	Erling Tveit Stian Boretti	7–6(7–2), 7–6(7–5), 7–5	Win
	QF	7-10-2010		Bulgaria	Clay	Grigor Dimitrov Ivaylo Traykov	6–7(3–7), 7–6(7–2), 7–6(14–12), 6–3	Win
	SF	9-18-2010		Lithuania	Hard (I)	Ričardas Berankis Laurynas Grigelis	7–5, 6–4, 1–6, 3–6, 3–6	Loss
2011 Europe/Africa Zone Group I	1R	3-05-2011	Luka Gregorc	Finland	Clay (I)	Harri Heliövaara Jarkko Nieminen	6–7(5–7), 6–4, 6–4, 7–5	Win
	2R	7-09-2011	Blaž Kavčič	Italy	Clay	Simone Bolelli Daniele Bracciali	6–7, 6–7, 2–6	Loss
2012 Europe/Africa Zone Group I	1R	2-11-2012	Blaž Kavčič	Denmark	Hard (I)	Thomas Kromann Frederik Nielsen	6–4, 6–7, 6–4, 7–5	Win
	2R	4-07-2012	Blaž Kavčič	South Africa	Hard	Raven Klaasen Izak van der Merwe	7–6(7–5), 6–7(4–7), 1–6, 4–6	Loss
2013 Europe/Africa Zone Group I	1R	2-02-2012	Blaž Kavčič	Poland	Hard (I)	Mariusz Fyrstenberg Marcin Matkowski	6–3, 2–6, 6–2, 4–6, 13-11	Win