The world No. 1 has dropped just eight games through her first three matches to reach the quarterfinals of the Mutua Madrid Open for a second straight year.

No. 1-ranked Iga Swiatek led Poland into the quarterfinals by winning singles and mixed doubles alongside Hubert Hukacz vs. Spain.

Katie Boulter and Cameron Norrie helped Britain beat host Australia on the opening day of the United Cup tennis tournament, while Spain won the decisive mixed double to edge Brazil 2-1.

The women's competition is set to launch Tuesday in Seville.

The Aussie scored his second Top 10 win of the season with a 6-3, 6-4 victory Monday.

Medvedev will next face Alexander Zverev for the fifth time this year, with both bidding for a final berth.

Last year's WTA Newcomer of the Year battled past Mayar Sherif in three sets Saturday.

The tennis world has been critical of Sorribes Tormo and partner Marie Bouzkova, who were seen as pushing for a default after an errant shot from Kato struck a ball girl in doubles on Sunday.

After tournament referee Remy Azemar and Grand Slam supervisor Wayne McEwen went to Court 14 to look into what happened, Kato and her partner were disqualified.

Kato, a Japanese player, struck a ball at the conclusion of a point that inadvertently hit a ball girl at the back of the court.