section_path: Career/2019: Singles top 10, doubles No. 2/Doubles: US Open title, Sunshine Double
section_name: Doubles: US Open title, Sunshine Double
paragraph_text: Doubles: US Open title, Sunshine Double
  
  Sabalenka started the year ranked No. 73 in doubles. She began partnering with Elise Mertens in January, when the pair lost to top seeds Barbora Krejčíková and Kateřina Siniaková in the third round of the Australian Open. They had their breakthrough in March at the two Premier Mandatory tournaments. In only their second tournament together, Sabalenka and Mertens won the Indian Wells Open. They defeated three of the top five seeds in the event, including second seeds Tímea Babos and Kristina Mladenovic in the first round and top seeds Krejčíková and Siniaková in the final. The pair matched this success at their next event by winning the Miami Open to complete the Sunshine Double. They defeated three of the top six seeds, including third seeds Hsieh Su-wei and Barbora Strýcová in the second round. They won the final against sixth seeds Samantha Stosur and Zhang Shuai. With these two titles, Sabalenka rose to No. 21 in the world.
  
  Sabalenka and Mertens continued to partner together throughout the year, entering eleven events before the year-end championships. Sabalenka did not have much success in the Grand Slam singles events, but she produced much better results in doubles. Sabalenka and Mertens reached the semifinals at the French Open, losing to second seeds Babos and Mladenovic. They then reached the quarterfinals at Wimbledon, losing to third seeds Hsieh and Strýcová. These were Sabalenka's first two appearances in at least the quarterfinals at a Grand Slam event. Sabalenka and Mertens had their best result of the year at the US Open. As the fourth seed at the event, they made it to the final without playing another top-ten-seeded team. In the final, they faced eighth seeds Victoria Azarenka and Ashleigh Barty, the latter of whom had won the title a year earlier with CoCo Vandeweghe. Sabalenka and Mertens defeated Azarenka and Barty in straight sets for their first Grand Slam title in any discipline. With this title, Sabalenka made her top 10 debut in doubles at No. 6 in the world.
  
  Sabalenka and Mertens made one more final during the year, finishing runner-up at the Wuhan Open, where Sabalenka won the singles title. Their three big titles helped them win the Race to Shenzhen and qualify for the WTA Finals as the top seeds. Before the event, Sabalenka and Mertens moved up to No. 2 and No. 3 in the rankings, respectively, behind only world No. 1, Barbora Strýcová. At the WTA Finals, the pair were placed in a round robin group with third seeds Babos and Mladenovic, fifth seeds Chan Hao-ching and Latisha Chan, as well as eighth seeds Anna-Lena Grönefeld and Demi Schuurs. In their opening match, they were upset by Grönefeld and Schuurs in a match tiebreak. After defeating the Chan sisters, Sabalenka and Mertens lost to Babos and Mladenovic in another match tiebreak. They did not advance out of their group.
  
  Sabalenka started the year ranked No. 73 in doubles. She began partnering with Elise Mertens in January, when the pair lost to top seeds Barbora Krejčíková and Kateřina Siniaková in the third round of the Australian Open. They had their breakthrough in March at the two Premier Mandatory tournaments. In only their second tournament together, Sabalenka and Mertens won the Indian Wells Open. They defeated three of the top five seeds in the event, including second seeds Tímea Babos and Kristina Mladenovic in the first round and top seeds Krejčíková and Siniaková in the final. The pair matched this success at their next event by winning the Miami Open to complete the Sunshine Double. They defeated three of the top six seeds, including third seeds Hsieh Su-wei and Barbora Strýcová in the second round. They won the final against sixth seeds Samantha Stosur and Zhang Shuai. With these two titles, Sabalenka rose to No. 21 in the world.
  
  Sabalenka and Mertens continued to partner together throughout the year, entering eleven events before the year-end championships. Sabalenka did not have much success in the Grand Slam singles events, but she produced much better results in doubles. Sabalenka and Mertens reached the semifinals at the French Open, losing to second seeds Babos and Mladenovic. They then reached the quarterfinals at Wimbledon, losing to third seeds Hsieh and Strýcová. These were Sabalenka's first two appearances in at least the quarterfinals at a Grand Slam event. Sabalenka and Mertens had their best result of the year at the US Open. As the fourth seed at the event, they made it to the final without playing another top-ten-seeded team. In the final, they faced eighth seeds Victoria Azarenka and Ashleigh Barty, the latter of whom had won the title a year earlier with CoCo Vandeweghe. Sabalenka and Mertens defeated Azarenka and Barty in straight sets for their first Grand Slam title in any discipline. With this title, Sabalenka made her top 10 debut in doubles at No. 6 in the world.
  
  Sabalenka and Mertens made one more final during the year, finishing runner-up at the Wuhan Open, where Sabalenka won the singles title. Their three big titles helped them win the Race to Shenzhen and qualify for the WTA Finals as the top seeds. Before the event, Sabalenka and Mertens moved up to No. 2 and No. 3 in the rankings, respectively, behind only world No. 1, Barbora Strýcová. At the WTA Finals, the pair were placed in a round robin group with third seeds Babos and Mladenovic, fifth seeds Chan Hao-ching and Latisha Chan, as well as eighth seeds Anna-Lena Grönefeld and Demi Schuurs. In their opening match, they were upset by Grönefeld and Schuurs in a match tiebreak. After defeating the Chan sisters, Sabalenka and Mertens lost to Babos and Mladenovic in another match tiebreak. They did not advance out of their group.