Polona Hercog (Slovene pronunciation: [pɔˈlóːna ˈxèːɾtsɔk], born 20 January 1991) is a Slovenian professional tennis player. Her career-high WTA rankings are world No. 35 in singles and No. 56 in doubles. She has won five titles on the WTA Tour, three in singles and two in doubles. Hercog also has had success on the ITF Women's Circuit, winning 19 singles and five doubles titles.
Partnering with Jessica Moore, she won the French Open and Wimbledon junior titles in the doubles competition in 2008.
Hercog was born in Maribor, Slovenia, to florist Romana and bar owner Vojko. As a four-year-old she began playing in the local tennis clinic opened by Mima Jaušovec, and at age 14 moved to Italy to train professionally. Hercog is fluent in Slovenian, English, and Italian, and cites Justine Henin as her role model. She currently resides in Doha, Qatar and practises in Budapest.
In September 2007, Hercog received a wildcard and made her WTA Tour debut at the Slovenia Open, losing to Elena Vesnina in three sets.
2008: Juniors doubles majors & first ITF Circuit titles
Hercog reached the singles quarterfinals at both the junior French Open and Wimbledon. In doubles, she and Australian Jessica Moore won two Grand Slam titles together, the French Open and Wimbledon; the latter was the final tournament of her junior career. On 7 July, Hercog achieved a career-high ITF junior ranking of No. 8.
In early 2008, she also won two ITF titles ($10k) and reached the final of a $25k event. Hercog then participated in the İstanbul Cup, coming through qualifying to reach the main draw, where she lost in the first round to eighth seed Tsvetana Pironkova. At the same tournament, she reached the final of the doubles competition partnering with New Zealand's Marina Erakovic. Ranked No. 215, she made her Grand Slam debut in the qualifying competition of the US Open, losing to Sandra Záhlavová in the first round.
In April 2009, Hercog entered the Morocco Open in Fez via qualifying, defeating seventh seed Roberta Vinci to reach the quarterfinals, where she lost to second seed Alisa Kleybanova. At that year's French Open, she qualified for the main draw and upset 23rd seed Kleybanova before losing to Aravane Rezaï in the second round. On 5 July, she debuted in the top 100 of the rankings for the first time at No. 89. At the US Open, Hercog was beaten by American wildcard Christina McHale in the first round. She also played the Luxembourg Open, defeating Maria Elena Camerin in the opening round. She then lost to Sabine Lisicki in two sets. Hercog reached the second round of the 2009 Allianz Cup in Sofia, losing to Bojana Jovanovski.
Hercog began her season at the Auckland Open where she lost to Shahar Pe'er in the first round.
At the Mexican Open in Acapulco, Hercog reached her first WTA Tour singles final and won her first WTA doubles title. She defeated Rossana de los Ríos in the first round, Alizé Cornet in the second, Ágnes Szávay retired from the quarterfinals match when Hercog was leading by a set, and Carla Suárez Navarro in two sets in the semifinals. In the final, she lost to top seed and former world No. 1, Venus Williams, despite winning the first set. Partnering with Barbora Záhlavová-Strýcová, she won her first tour doubles title, beating the Italian duo Sara Errani and Roberta Vinci.
At the Indian Wells Open, Hercog defeated Raluca Olaru in the first round and was defeated by 11th seed Marion Bartoli in the second round.
She caused an upset in the second round of the French Open by defeating No. 24, Lucie Šafářová.
In Portorož, she reached the semifinals, was up a set against Anna Chakvetadze but then lost the match in three sets.
Seeded sixth at the Danish Open in Copenhagen, she had a chance to take revenge on Anna Chakvetadze as they met in the quarterfinals. Hercog lost the match, this time in straight sets.
Hercog began the year at the Brisbane International where she lost in the first round to Iveta Benešová in two sets. Seeded second in qualifying at the Sydney International, Hercog lost in the first round to Jill Craybas. At the Australian Open, she lost in the first round in a close match to world No. 46, Anastasija Sevastova.
After the Australian Open, Hercog played at the 2011 Fed Cup World Group II against Germany. She defeated Julia Görges, however, she lost to Andrea Petkovic in straight sets. Slovenia lost to Germany 1–4. Seeded second at the Copa Colsanitas, she defeated Pauline Parmentier in the first round. In the second round, she lost to Petra Martić. Seeded second at the Abierto Mexicano, Hercog lost in the first round to Lourdes Domínguez Lino. She then stayed in Mexico for the Monterrey Open. Seeded eighth, Hercog defeated Angelique Kerber in the first round 6–3, 6–3. She then reached the semifinals where she lost to top seed Jelena Janković in two sets. At the Indian Wells Open, Hercog lost in the first round to Anastasija Sevastova. At the Miami Open, she lost in the first round to Chanelle Scheepers in three sets.
Hercog began her clay-court season at the Andalucia Tennis Experience. She lost in the first round to Laura Pous Tió, 1–6, 2–6. Next, Hercog played at the Morocco Open where she got revenge on Chanelle Scheepers by defeating her in the first round. However, she withdrew from her second-round match against Melanie Oudin due to an ankle injury. At the Barcelona Open, Hercog won her first-round match against lucky loser Jamie Hampton. In the second round, she easily beat Mirjana Lučić. In the quarterfinals, she lost to Laura Pous Tió in three sets.
Hercog began the year at the Brisbane International. She retired trailing 6–1, 4–1 in her first-round match against seventh seed Anastasia Pavlyuchenkova due to a low back injury. Seeded third in qualifying at the Sydney International, Hercog lost in the final round of qualifying to seventh seed Ekaterina Makarova. However, she received a lucky loser spot into the main draw. In the first round, Hercog lost to eighth seed Marion Bartoli. At the Australian Open, she lost in the first round to 22nd seed Julia Görges.