Second seed Elena Dementieva made a confident start to her claycourt campaign as she beat compatriot Alina Jidkova 6-4, 6-4 on Tuesday to reach the third round of the Family Circle Cup.
But there was a surprise defeat for another Russian as sixth seed Vera Zvonareva let slip a 4-1 final set lead against Iveta Benesova of the Czech Republic to go out.
Dementieva, who missed last week's Amelia Island Championship because of a hip injury, wore strapping to her right thigh, but showed no signs of discomfort and seemed to enjoy her return to clay.
Jidkova broke to lead 3-1 but the 23-year-old Dementieva, runner-up at both the French and US Opens last year, won four of the next five games to take the set.
Dementieva sent down 11 double faults but her serve, so often the weak point of her game in the past, was much improved and she clinched victory with a deft drop shot.
"I felt very confident today on the court," she said.
"I like to play on the clay courts, and I had the rest last week, so I feel pretty fresh. I was ready for this match and I really enjoyed today."
Earlier, Zvonareva, the world number 10, recovered from a set and a break down against Benesova to level the match at one set apiece.
But she lost her way as the left-handed Czech, world-ranked 51, held her nerve to win 6-4, 4-6, 7-5 and progress to a meeting with either former world number one Justine Henin-Hardenne of Belgium or Peng Shuai of China in round three.
Seventh-seeded Russian Nadia Petrova had no such trouble, cruising into round three with a 6-4 6-0 win over Akiko Morigami of Japan.
In first-round action, former champion Mary Pierce outclassed unseeded American Mashona Washington 6-3 6-2
Pierce, who won the title in 2000, the same year she won the French Open, was too consistent for Washington and now faces Nuria Llagostera Vives of Spain, with the winner to face Dementieva in round three.
"It was a bit of a weird match," Pierce said.
"I started really strong and she was maybe feeling the pressure and made a lot of errors. At the end, though, she started playing really well."
Number 15 seed Pierce broke Washington twice in overcast, cool conditions on the way to taking the opening set.
The 30-year-old Frenchwoman then broke twice for a 3-0 lead in the second set to all but settle the match.
Since the Australian Open Pierce has been beaten only by players ranked in the top four and the winner of two grand slam titles said she is building well towards the French Open.
"The French is my favourite tournament," said Pierce.
"It's definitely my goal of the clay court season, if not of the year, and I'm feeling good and really excited.
French 17-year-old Tatiana Golovin, seeded 13, crushed American Amy Frazier 6-3 6-3 to reach round two but compatriot Virginie Razzano, a semi-finalist last week at Amelia Island, was hammered 6-3 6-0 by Lisa Raymond.
Shinobu Asagoe, the 14th seed from Japan, also advanced to round two but Australian Alicia Molik, the fifth seed, withdrew because of an inner ear infection.
"I feel like my body isn't allowing me to play so I can't fight that," she said.
Molik is due to return for the German Open in Berlin, which begins on May 2.