Indian Wells, USA: World number one Naomi Osaka on Saturday launched her Indian Wells title defense with a 6-3, 6-4 victory over 65th-ranked Kristina Mladenovic of France.
Osaka, whose second straight Grand Slam title at the Australian Open in January propelled her to the top of the rankings, avenged a loss to Mladenovic in Dubai last month in her first match since she lifted the trophy in Melbourne.
It wasn't all smooth sailing as Osaka was broken when serving for the match at 5-2 in the second.
After Mladenovic held serve to narrow the deficit to 5-4, the Japanese player faced another break point before wrapping up the match after one hour and 21 minutes.
"I've never been a defending champion before -- that's new and I was really nervous," said Osaka, whose first WTA title at Indian Wells last year launched a 2018 campaign that would eventually include her first Grand Slam crown at the US Open.
Osaka next faces Danielle Collins, the 25th-seeded American who beat Belgian Kirsten Flipkens, 6-4, 6-1.