PARIS, France - Karin Knapp came full circle at Roland Garros on Tuesday, earning her first career Top 10 win over Victoria Azarenka a decade after defeating the former No.1 at this very tournament back in 2006, 6-3, 6-7(6), 4-0 ret.
Close to a double-break lead in the opening set, Azarenka struggled beneath Knapp's weight of shot for most of the match, losing five games in a row to fall behind a set to the Italian. Knapp had been dealing with a right knee issue for most of 2016, but it was the Belarusian who took a medical time out in the middle of the second set for that very issue.
Fighting through episodes of discomfort, Azarenka twice broke Knapp as she served for the match, and saved a match point in the ensuing tie-break with a screaming winner to push the contest into a deciding set.
Knapp raced out to a quick 4-0 lead from there as the pain became more apparent from Azarenka, who was forced to retire. By match's end, the Italian had hit 34 winners to 24 unforced errors, while the stats were essentially reversed for her injured opponent (23 winners, 36 unforced).
"Heading into the match today I was feeling fine. I was ready to play," Azarenka said in a statement after the match. "But I started to feel a sharp pain in my right knee. I've had an injury there before, a while ago, but it hasn't been a problem until today. At first it was on and off and I was able to win the tie-break, but then it got worse as the match went on, and unfortunately there was nothing i could do.
"I haven't made any plans yet for the days ahead, but will have treatment and can only look forward to playing Roland Garros next year."
Up next for Knapp is Anastasija Sevastova, who eased past American qualifier Sachia Vickery, 6-2, 6-2. No.28 seed Andrea Petkovic also advanced into the second round with a 6-2, 6-2 win over Laura Robson, who was playing her first major tournament of the season.