Naomi Osaka
Japan's Naomi Osaka serves to Croatia's Donna Vekic during their Porsche tennis Grand Prix match in Stuttgart, Germany, on Friday. Image Credit: AP

Stuttgart: World No. 1 Naomi Osaka came from behind in the final set to beat Croatian Donna Vekic 6-3, 4-6, 7-6(4) on Friday and move into the Porsche Tennis Grand Prix semi-finals.

Osaka comfortably won the opening set but was tested by the Croatian, who pushed her to the limit in the second and third. The Japanese made 45 unforced errors as she struggles to get to grips with swapping hard courts for clay.

Osaka was visibly frustrated and trailed 5-1 in the final set but she refused to give up and found her rhythm to break Vekic twice and prevent her from serving for the match.

In the tiebreaker, a confident Osaka upped her baseline game and had two early mini breaks before wrapping up the match in two hours and 18 minutes. An infuriated Vekic even smashed her racket after losing the match.

“I told myself I didn’t want to have any regrets here,” Osaka said. “I was stressed out when I went down 1-5 ... but this (comeback) was pretty good because I don’t play really well on clay.” Earlier, world No. 3 Petra Kvitova came back from a set down to beat Anastasija Sevastova 2-6 6-2 6-3 and move into the tournament’s semi-finals for the third time in her career.

Sevastova broke Kvitova twice to take a 3-0 lead as the Czech struggled with her first serve and made a slew of unforced errors.

Kvitova fought back in the second set and won 10 straight points before levelling the match.