Kayla Day
Kayla Day is an American professional tennis player. In 2016, she won the Junior US Open and the USTA Girls 18s National Championships.
Junior career
Day has been No. 1 in the girls' 12s, 14s, 16s, and 18s US national rankings. In 2016, she climbed to No. 1 in the ITF junior rankings by winning the Junior US Open, reaching the semifinals at Wimbledon, and reaching the final at the Orange Bowl the previous year. She also won the 2016 USTA Girls 18s National Championships to earn a wild card into the main draw of the US Open.Professional career
2016
Day made her WTA debut at the 2016 Connecticut Open in New Haven after reaching the main draw as a lucky loser, having defeated Naomi Broady and Kirsten Flipkens along the way. The following week, she played in her first career Grand Slam at the US Open and won her first match against compatriot Madison Brengle.Shortly after turning 17, Day won her first career title at a $50,000 tournament in Macon. The following week at Scottsdale, she reached the semifinals to enter the top 200 for the first time. With her combined performance at these two events, Day won the Australian Open Wild Card Challenge to earn a spot in the main draw at the first Grand Slam event of 2017.
2017
Day picked up her first WTA wins of the season — and first wins of her career at a Premier Mandatory event — at the BNP Paribas Open in Indian Wells, including a victory over 2017 Australian Open semifinalist Mirjana Lučić-Baroni to reach the third round of the tournament.Personal
Day started playing tennis when she was seven years old. Her mother is from the Czech Republic.Grand Slam singles performance timeline
| Tournament | 2016 | 2017 | 2018 | 2019 | 2020 | SR | W–L | Win % |
| Australian Open | A | 1R | Q3 | A | A | 0 / 1 | 0–1 | |
| French Open | A | Q2 | Q1 | A | 0 / 0 | 0–0 | ||
| Wimbledon | A | Q1 | A | A | 0 / 0 | 0–0 | ||
| US Open | 2R | 1R | Q1 | A | 0 / 2 | 1–2 | ||
| Win-Loss | 1–1 | 0–2 | 0–0 | 0–0 | 0–0 | 0 / 3 | 1–3 |
ITF Circuit finals
Singles: 3 (1 title, 2 runner–ups)
| Result | W–L | Date | Tournament | Tier | Surface | Opponent | Score |
| Loss | 0–1 | May 2016 | ITF Naples, United States | 25,000 | Clay |  Valeria Solovyeva | 4–6, 0–6 |
| Win | 1–1 | Oct 2016 | ITF Macon, United States | 50,000 | Hard |  Danielle Collins | 6–1, 6–3 |
| Loss | 1–2 | Feb 2017 | ITF Rancho Santa Fe, United States | 25,000 | Hard |  Bianca Andreescu | 4–6, 1–6 |
Doubles: 3 (2 title, 1 runner–up)
| Result | W–L | Date | Tournament | Tier | Surface | Partner | Opponents | Score |
| Loss | 0–1 | Feb 2017 | ITF Midland, United States | 100,000 | Hard | Caroline Dolehide | Ashley Weinhold Caitlin Whoriskey | 6–7, 3–6 |
| Win | 1–1 | Feb 2017 | ITF Rancho Santa Fe, United States | 25,000 | Hard | Caroline Dolehide |  Anhelina Kalinina Chiara Scholl | 6–3, 1–6, |
| Win | 2–1 | Feb 2019 | ITF Rancho Santa Fe, United States | 25,000 | Hard | Sophia Whittle |  Eudice Chong  You Xiaodi | 6–2, 5–7, |