(Reuters) - Bianca Andreescu's dominant recent impressive run ended at the Miami Open as the Canadian teenager who has taken the tennis world by storm retired with a shoulder injury while trailing 6-1 2-0 in her fourth-round clash with Estonia's Anett Kontaveit.
The 18-year-old arrived in Miami fresh off her triumph at Indian Wells, where she became the first wildcard to win the prestigious event, but an overworked right shoulder ended any hopes of extending her 10-match winning streak.
Up next for Kontaveit in the last eight will be Taiwan's Hsieh Su-wei, who burnished her reputation as a giant slayer by taking down Denmark's Caroline Wozniacki 6-3 6-7(0) 6-2 after beating world number one Naomi Osaka in the previous round.
It was 33-year-old Hsieh's first win over former world number one Wozniacki in five attempts.
Second seed Simona Halep broke Venus Williams (NYSE:WMB) in the first game of their match and never looked back as she coasted to a 6-3 6-3 victory to book her ticket to the quarter-finals.
Halep smacked a forehand winner down the line to seal the convincing victory and keep her hopes of regaining the world number one spot alive.
Czech third seed Petra Kvitova beat Frenchwoman Caroline Garcia 6-3 6-3 to set up a last-eight clash with Australian 12th seed Ashleigh Barty, a 4-6 6-3 6-2 winner over seventh seed Kiki Bertens of the Netherlands.
INJURY SETBACKS
After losing the first set, Andreescu, who has dealt with several injury setbacks in her young career, called for the trainer to work on her shoulder, something she did three times during her third-round clash with Angelique Kerber.
The Canadian, who had struggled throughout the match, tried to carry on but half-heartedly played a Kontaveit serve and then started walking off the court only to casually swat aside a return before signaling to the chair umpire that she was done.
"I have played so many matches. I guess this is just a way of my body telling me that it's had enough," she told reporters, adding that she would not compete at next month's Charleston Open to give herself some time to recover.
"It's disappointing, but it's part of the sport."
Kerber, who also lost to Andreescu in the Indian Wells final, called the teenager "the biggest drama queen ever" during their post-match handshake in Miami before going on Twitter and crediting the Canadian for a great performance.
Monday's loss dropped Andreescu, who is ranked 24th in the world after starting the year at 152nd, to 31-4 for the season. Her 35 matches is the highest total on the WTA Tour this season.