Injury forces Serena Williams to retire against Muguruza

California, March 11: Serena Williams' Indian Wells Open campaign ended in retirement after the 23-time grand-slam winner complained of a left-leg injury midway through her match with Garbine Muguruza.

Williams made a solid start to Sunday's contest in California as she raced into a 3-0 lead, the 10th seed dominating from the baseline with a string of powerful forehands.

However, the 37-year-old was was not moving freely and Muguruza battled back with a series of stunning groundstrokes of her own.

Muguruza reeled off six successive games to take the first set but Williams' mobility was well short of her best, and her retirement seemed inevitable at the changeover.

Having called for the trainer, Williams complained of a pain in her left leg but tried to battle on at the start of the second set.

Serena had a lengthy discussion with the trainer and doctor. The trainer took the blood pressure cuff out but didn’t use it. No MTO taken, back underway. https://t.co/6DoQptia6C

— WTA Insider (@WTA_insider) March 10, 2019

Muguruza held to love with Williams not even trying to run for the game-winning point and on her return to the chair the American was noticeably breathing heavily.

She quickly called time on proceedings, handing Muguruza a place in the last 16 – where she will meet Kiki Bertens or Johanna Konta.