Emma Raducanu rounded out a day of British success at the Madrid Open, with wins too for Dan Evans and wildcard Jack Draper.
US Open champion Raducanu, 19, dominated Ukraine's Marta Kostyuk to win 6-2 6-1.
Evans won only his second clay court match of the season, beating Argentina's Federico Delbonis 6-3 6-4 in the first round.
Wildcard Draper beat accomplished clay-courter Lorenzo Sonego 6-4 6-3.
Raducanu, who is playing her first clay court season, advances to the third round to face another Ukrainian, Anhelina Kalinina.
"I'm definitely happy with my performance," said Raducanu.
"Marta's a great opponent - I knew it was going to be a really tough battle. I went out there trying to be really aggressive and it paid off."
The British number one split with her coach Torben Beltz, after just five months, and is working with LTA head of women's coaching Iain Bates this week.
Evans will face either Jenson Brooksby or Roberto Bautista Agut in round two, while Draper will face Russian sixth seed Andrey Rublev.
British men's number one Cameron Norrie will face Korean qualifier Kwon Soonwoo in his first-round match on Monday.
Wildcard Andy Murray, a two-time Madrid Open champion, will start his campaign against Austria's Dominic Thiem, who is returning from a wrist injury.