Caty McNally

McNally made her WTA Tour main-draw debut at the 2017 Western & Southern Open in the doubles tournament, partnering with Alexa Glatch.

In February 2019, McNally won the $100k Dow Tennis Classic. Later that month, she reached the third round of the Indian Wells Challenger, losing to eventual winner Viktorija Golubic. A week after that, she qualified for the Indian Wells Open, also in Indian Wells, beating Kristýna Plíšková and Timea Bacsinszky in the qualifiers. She earned a wildcard for the Miami Open, where she was again beaten by Coco Gauff. In July, she qualified for her first Grand Slam main-draw at Wimbledon.

At the end of July and beginning of August, McNally recorded her first WTA Tour main-draw singles wins with a run to the semifinal at the Washington Open, beating Zhu Lin, Christina McHale and fourth seed Hsieh Su-wei. Meanwhile, she and Gauff won the doubles competition, beating third seeds Miyu Kato and Anna Kalinskaya in the semifinal, and fourth seeds Maria Sanchez and Fanny Stollár in the final. She was awarded a wildcard into her home tournament, the Cincinnati Open, where she played her first-round match on center court, but lost to Elise Mertens. She teamed with up Alison Riske to play in the doubles. The pair reached the quarterfinals, beating fourth seeds Xu Yifan and Gabriela Dabrowski in a second round match that went to 17–15 in the match tiebreak, the second-longest match tiebreak in a women's doubles match.

McNally's first win in a major came at the US Open where she defeated Timea Bacsinszky in the first round. She took a set off six-times champion Serena Williams before losing in three sets in a tight second-round match. Passing her in the stadium complex later that night, Williams asked her: "Are you really 17 years old?" McNally and Gauff—dubbed "McCoco"—followed up their 2018 girls' doubles win by reaching the third round of the doubles event, beating ninth seeds Nicole Melichar and Kveta Peschke in the second round in a packed Louis Armstrong Stadium, but losing heavily to Ash Barty and Victoria Azarenka in the third. The run took McNally into the top 100 in the doubles rankings, and just outside the top 100 in the singles rankings.

She partnered Gauff again for the Linz Open, where they reached the semifinal. They were beaten by Barbara Haas and Xenia Knoll. At Luxembourg the following week, McNally lost in the first round to Jeļena Ostapenko, but went through to the final of the doubles with Gauff, beating Misaki Doi and Makoto Ninomiya, No. 4 seeds Anna Blinkova and Miyu Kato, and top-seeded pair of Kristýna Plíšková and Renata Voráčová. They beat second seeds Kaitlyn Christian and Alexa Guarachi in the final to secure their second WTA tournament title, with a career win–loss record of 12–2 as a team.

In her first tournament of 2020, the Auckland Open, McNally was knocked out in the first round of the singles after qualifying as a lucky loser, but she and Gauff reached the semifinals of the doubles. At the Australian Open, she won her qualifying matches, entering the main draw, where she defeated Sam Stosur in the first round, before losing to Zhang Shuai. In doubles, McNally and Gauff recorded their best result at a Grand Slam tournament, reaching the quarterfinals before falling to second seeded Kristina Mladenovic and Tímea Babos in two sets. As a result, McNally broke into the top 40 in the doubles rankings. In March, she lost to Sachia Vickery in the first round of the Indian Wells Challenger tournament, but teamed up with Jessica Pegula to reach the final of the doubles, beating third seeds Stosur and Yanina Wickmayer in the semifinal before falling to Asia Muhammad and Taylor Townsend in the final.

Following the break caused by the COVID-19 pandemic, McNally took part in the Western & Southern Open, which was moved from her home town of Cincinnati to New York, losing in the first round to Alizé Cornet. The following week, she reached the third round of a Grand Slam tournament for the first time when she beat 21st seed Ekaterina Alexandrova in the second round of the US Open.

McNally made her World TeamTennis debut in 2020, playing for the Springfield Lasers.

McNally reached her second consecutive doubles quarterfinal at the Australian Open, again playing with Gauff. They beat sixth seeds Gabriela Dabrowski and Bethanie Mattek-Sands, and ninth seeds Alexa Guarachi and Desirae Krawczyk, before falling to fourth seeds Nicole Melichar and Demi Schuurs. The pair then reached the quarterfinal of the Miami Open, beating second seeds Barbora Krejčíková and Kateřina Siniaková in the round of 16.

In April, McNally reached the third round of the Charleston Open, beating Elena Rybakina and Anastasija Sevastova in the first two rounds. In the one-off MUSC Health Open later that month, also in Charleston, she was beaten in the first round of the singles by Shelby Rogers, but partnered with Hailey Baptiste to win the doubles tournament, beating Australian duo Ellen Perez and Storm Sanders in the final. She won her second doubles title of the season the following month at the Emilia-Romagna Open, partnering Gauff, who also won the singles. In August, she lost to Sloane Stephens in the first round of the Silicon Valley Classic, but reached the semifinal of the doubles with CoCo Vandeweghe.

McNally received a wildcard entry to the US Open, but was beaten in the first round by fourth seed Karolína Plíšková. In the women's doubles, McNally and Gauff, who were seeded 11th, made their deepest run yet in a Grand Slam tournament when they reached the semifinals without dropping a set, beating top seeds and current Wimbledon champions Hsieh Su-wei and Elise Mertens, in straight sets in the quarterfinals. They progressed to the final when their semifinal opponents, Luisa Stefani and Gabriela Dabrowski, retired after Stefani sustained an injury during the first set tiebreak. In the final, they lost to Sam Stosur and Zhang Shuai. The run to the final lifted McNally to No. 22 in the WTA doubles rankings.

At the St. Petersburg Trophy in February, McNally teamed up with Anna Kalinskaya to win the doubles title, beating Polish Alicja Rosolska and New Zealander Erin Routliffe in the final; it was her fifth on the WTA Tour. The win took her to a career high No. 16 in the rankings on February 14, 2022.

She reached a second doubles final for the season with Kalinskaya at the Washington Open, defeating second seeded Belgian pair of world No. 1 in doubles, Elise Mertens, and Greet Minnen. They lost in the final to top seeded Jessica Pegula and Erin Routliffe.

At the US Open, she and Taylor Townsend reached the doubles final, losing to Krejčíková and Siniaková. At the Ostrava Open the following month, she reached the quarterfinals of the singles before being beaten by Iga Świątek. In doubles, she teamed up with Alycia Parks for the first time. They were unseeded, but beat the first and fourth seeds en route to the final, where they beat third seeds Rosolska and Routliffe to win the title. It was McNally's sixth doubles title.

In November, she won her first WTA 125 title at the Midland Classic defeating Anna-Lena Friedsam in straight sets and made her top 100 debut in singles, at world No. 94 on November 7, 2022.

At the Mérida Open, McNally reached her first WTA Tour semifinal defeating third seed Zhu Lin, Katie Volynets and Kimberly Birrell. She then lost to qualifier Rebecca Peterson. As a result, she reached the top 75, rising 17 positions. At the same tournament, playing with Diane Parry, she won her seventh doubles title, beating Wang Xinyu and Wu Fang-hsien in the final.

In what turned out to be her last event of the season, McNally lost in the first round at Wimbledon to Jodie Burrage. An elbow injury subsequently forced her to withdraw from the US Open.

McNally withdrew from the Australian Open. She briefly returned to the tour in February, playing at the Transylvania Open, where she won the doubles title with Asia Muhammad, as well as tournaments in Linz and Puerto Vallarta, before undergoing surgery on her elbow at the renowned Andrews Sports Medicine and Orthopaedic Center in Alabama in March.

She made her comeback in November 2024 at the WTA 125 Dow Tennis Classic in Midland, Michigan, defeating Leonie Küng in the first round, before losing her next match to Alycia Parks.

The following month, McNally won her first title since her return to action at the Tampa W50 event, and as a result, jumped 223 places in the WTA singles rankings to world No. 543.

Using her protected ranking to gain entry into the main-draw at the Australian Open, McNally lost to Varvara Gracheva in the first round. Again competing under her protected ranking, she entered the WTA 1000 event at Indian Wells and advanced to the second round when her opening match opponent, Ajla Tomljanović, retired after McNally won the first set. She lost her next match to 24th seed Liudmila Samsonova. At the Miami Open, she once more entered the main draw using her protected ranking, but lost in the first round to Viktoriya Tomova in three sets.

McNally qualified for the Charleston Open and defeated Anhelina Kalinina in the first round, before losing to 14th seed Anna Kalinskaya in her next match.

At Wimbledon, McNally once again used her protected ranking to gain entry into the main-draw and overcame wildcard entrant Jodie Burrage in the first round.