2019: Return to the top 10 Williams started her 2019 season at the Australian Open, her first appearance at the tournament since winning it in 2017. Seeded 16th, she defeated Tatjana Maria, Eugenie Bouchard, and Dayana Yastremska in the first three rounds, then bested top seed and world No.1 Halep in the fourth. In the quarterfinals, she met Karolína Plíšková, who won the match after Williams twisted her ankle. This was Williams's earliest defeat at the Australian Open since her fourth-round loss in 2014. Despite the loss, her ranking climbed to No.11. Williams prevailed over Azarenka in the second round of the Indian Wells Masters, but a viral illness caused her to retire. She then experienced a recurrence of a long-term knee injury, which caused her to pull out of upcoming Miami and Rome events. She could not train properly until after the French Open, where she lost in the third round. Williams then reached the final at Wimbledon, making 2019 the 13th consecutive year in which she played in a Grand Slam final. She also became the oldest Grand Slam finalist in the Open Era. Williams lost the final to Halep in two straight sets.
2019: Return to the top 10 Williams started her 2019 season at the Australian Open, her first appearance at the tournament since winning it in 2017. Seeded 16th, she defeated Tatjana Maria, Eugenie Bouchard and Dayana Yastremska in the first three rounds, then bested top seed and world No.1 Halep in the fourth. In the quarterfinals, she met Karolína Plíšková, who won the match after Williams twisted her ankle. This was Williams's earliest defeat at the Australian Open since her fourth-round loss in 2014. Despite the loss, her ranking climbed to No.11. Williams prevailed over Azarenka in the second round of the Indian Wells Masters, but a viral illness caused her to retire. She then experienced a recurrence of a long-term knee injury which caused her to pull out of upcoming Miami and Rome events. She could not train properly until after the, French Open, where she lost in the third round. Williams then reached the final at Wimbledon, making 2019 the 13th consecutive year in which she played in a Grand Slam final. She also became the oldest Grand Slam finalist in the Open Era. Williams lost the final to Halep in two straight sets.