|Full name||Marcos Andres Giron|
|Country (sports)||United States|
|Residence||Thousand Oaks, California|
|Born||July 24, 1993|
Thousand Oaks, California, USA
|Height||5 ft 11 in (1.80 m)|
|Plays||Right-handed (two-handed backhand)|
|Career record||46-57 (44.7%)|
|Highest ranking||No. 49 (May 16, 2022)|
|Current ranking||No. 55 (July 25, 2022)|
|Grand Slam singles results|
|Australian Open||1R (2020, 2021, 2022)|
|French Open||3R (2021)|
|Wimbledon||2R (2021, 2022)|
|US Open||2R (2020, 2021)|
|Olympic Games||2R (2021)|
|Career record||6-9 (40.0%)|
|Highest ranking||No. 199 (July 1, 2019)|
|Current ranking||No. 218 (May 9, 2022)|
|Grand Slam doubles results|
|Australian Open||3R (2022)|
|French Open||1R (2022)|
|US Open||1R (2014, 2021)|
|Last updated on: May 9, 2022.|
Marcos Andres Giron (born July 24, 1993; Spanish: Marcos Girón) is an American professional tennis player. He achieved a career-high singles ranking of No. 49 on 16 May 2022 and a doubles ranking of No. 199 on July 1, 2019. He won the boys' singles in the Ojai Tennis Tournament in 2009 and the men's invitational in 2011. In 2014, Giron won the singles title at the 2014 NCAA Division I Tennis Championships for UCLA.
At the 2021 Halle Open, Giron reached his first quarterfinal at an ATP 500 level tournament as a qualifier where he was defeated by Félix Auger-Aliassime. As a result of this good run, he reached a then career-high of No. 65 on June 21, 2021.
In September at the 2021 Sofia Open, Giron reached his fourth quarterfinal of the season (with quarterfinal appearances in Halle, Metz and Winston-Salem) after defeating 3rd seed Alex de Minaur in the second round. He later beat 8th seed John Millman in 70 minutes to move into his first career ATP tour-level semifinal, where he lost to 2nd seed Gaël Monfils. As a result he reached a new career high ranking in the top 60 at world No. 59 on October 4, 2021.
At the 2022 Dallas Open, Giron beat Tennys Sandgren, Liam Broady, and 1st seed Taylor Fritz to reach his second ATP tour semifinal, where he lost to 4th seed Jenson Brooksby after holding four match points.
On his debut at the 2022 Italian Open, he reached the third round as a lucky loser after defeating 2020 Rome finalist, 12th seed and World No. 15 Diego Schwartzman. It was his best showing at a Masters 1000 on clay and the best clay court win of his career. This was his second win over Schwartzman, having defeated him as a qualifier at the 2021 Rolex Paris Masters, also in straight sets in the second round. He lost to Félix Auger-Aliassime in the third round. As a result he made his top 50 debut at World No. 49 on 16 May 2022.
Current through the 2022 Citi Open.
|Win||1-0||Sep 2013||USA F23, Claremont||Futures||Hard||Dennis Novikov||6-0, 7-5|
|Win||2-0||Sep 2013||USA F25, Laguna Niguel||Futures||Hard||Jarmere Jenkins||4-6, 6-1, 6-1|
|Win||3-0||Mar 2014||USA F9, Calabasas||Futures||Hard||Jason Jung||6-4, 4-6, 6-4|
|Loss||3-1||Nov 2014||Mexico F13, Mazatlán||Futures||Hard||Daniel Nguyen||0-6, 6-2, 6-7(0-7)|
|Win||4-1||Oct 2016||USA F33, Berkeley||Futures||Hard||André Göransson||5-7, 7-6(7-5), 6-4|
|Win||5-1||Jan 2017||USA F2, Long Beach||Futures||Hard||Collin Altamirano||7-6(7-3), 6-1|
|Loss||5-2||May 2017||China F7, Wuhan||Futures||Hard||Dayne Kelly||6-7(4-7), 6-7(6-8)|
|Win||6-2||May 2017||China F8, Fuzhou||Futures||Hard||Alexander Sarkissian||7-5, 6-4|
|Loss||6-3||Jul 2017||Canada F4, Saskatoon||Futures||Hard||Filip Peliwo||6-7(7-9), 7-6(7-5), 1-6|
|Loss||6-4||Mar 2018||USA F8, Calabasas||Futures||Hard||JC Aragone||2-6, 4-6|
|Win||7-4||Jan 2019||Orlando, USA||Challenger||Hard||Darian King||6-4, 6-4|
|Loss||7-5||Sep 2019||New Haven, USA||Challenger||Hard||Tommy Paul||3-6, 3-6|
|Win||8-5||Nov 2019||Houston, USA||Challenger||Hard||Ivo Karlovi?||7-5, 6-7(5-7), 7-6(11-9)|
|Loss||0-1||Sep 2012||USA F26, Irvine||Futures||Hard||Dennis Novikov|| Devin Britton
|Loss||0-2||Jun 2013||USA F17, Rochester||Futures||Clay||Dennis Novikov|| Chase Buchanan
|Win||1-2||Jul 2013||USA F18, Pittsburgh||Futures||Clay||Connor Smith|| Christopher Mengel
|Loss||1-3||Jul 2013||USA F20, Godfrey||Futures||Hard||Devin McCarthy|| Evan King
|Win||2-3||Sep 2013||USA F24, Costa Mesa||Futures||Hard||Mackenzie McDonald|| Keith-Patrick Crowley
|Loss||2-4||Jun 2015||Canada F3, Richmond||Futures||Hard||Farris Fathi Gosea|| Hunter Nicholas
|Win||3-4||Aug 2015||Canada F6, Saskatoon||Futures||Hard||Farris Fathi Gosea|| Patrick Davidson
|Win||4-4||Feb 2019||Dallas, USA||Challenger||Hard (i)||Dennis Novikov|| Ante Pavi?
|Win||5-4||Mar 2019||Indian Wells, USA||Challenger||Hard||JC Aragone|| Darian King
Giron's record against players who have been ranked in the top 10, with those who are active in boldface. Only ATP Tour main draw matches are considered:
|1.||Matteo Berrettini||10||Paris Masters, France||Hard (i)||2R||7-6 (7-3), 6-7 (0-7), 7-5||91|