Maria Sharapova continued her comeback from injury with a straight sets victory over Slovakia's Jarmila Groth at the LA Championships.
The Russian is still struggling for consistency after surgery on her shoulder, however she still had too much class for Groth as she recorded a 6-0 6-4 win.
"Her game plan was to attack from every single angle she could," said Sharapova.
"But she wasn't able to do that consistently because I was able to retrieve and make her hit more balls."
Having dominated the first set, Sharapova found herself under more pressure in the second set as Groth broke to lead 3-2.
However the 22-year-old broke straight back and then defended three break points before she ended Groth's resistance to love in the tenth game.
While Sharapova booked her place in the second round, three seeded players suffered early exits.
No.11 seed Virginie Razzano crashed out 7-6 (7-5) 6-3 to Anna Chakvetadze, 15th seed Kaia Kanepi lost 6-3 7-6 (7-4) to Lucie Safarova and 16th-ranked Francesca Schiavone was toppled by qualifier Jill Craybas 7-6 (9-7) 6-2.
Last year's runners up Flavia Pennetta, the No.10 seed, overcame a scare to beat Varvara Lepchenko 6-2 5-7 6-0.