MADRID — Canadian tennis stars Eugenie Bouchard and Milos Raonic advanced with big wins Wednesday at the Madrid Open.

Bouchard, from Westmount, Que., moved on to the women's quarter-finals after top-seed Angelique Kerber retired with a left thigh injury in the second set. Bouchard was leading 6-3, 5-0 when her German opponent pulled out.

While Kerber was clearly ailing, Bouchard was full value for the win. She hit 19 winners and won 7-of-9 break point opportunities. Bouchard will next face eighth seed Svetlana Kuznetsova of Russia on Thursday.

Bouchard, a former World No. 5, has shown glimpses of her old form in Madrid. She entered Wednesday's match coming off a statement victory over Maria Sharapova in the second round.

The Canadian has been vocally critical of Sharapova since the Russian star's return from a 15-month doping ban. Bouchard has called Sharapova a "cheater" who should have been banned for life.

Earlier Wednesday, Raonic moved on to the men's third round with a 6-4, 6-4 win over Luxembourg's Gilles Muller.

The world No. 6 from Thornhill, Ont., never faced break point and broke Muller twice on five opportunities. Raonic, seeded fifth in Madrid, will next face ninth seed David Goffin of Belgium on Thursday.

Raonic is playing in his second tournament since returning to action following a hamstring injury. He advanced to the final of the Istanbul Open last week before losing to Marin Cilic.