ST. PETERSBURG, Russia – No.4 seed Ana Ivanovic faced stiff opposition in talented young Russian, Margarita Gasparyan, but the Serb overcame the challenge in her opening match at the St. Petersburg Ladies Trophy to reach the quarterfinals, 7-5, 6-2.

Gasparyan made a splash to start the 2016 season, reaching the fourth round of the Australian Open, and kept things close in the opening set against Ivanovic, who fell in the third round in Melbourne to 2015 semifinalist Madison Keys.

“It was a very tough match,” she told former WTA star Ksenia Pervak during her on-court interview. “She played very well, I thought. I knew she’s had a very good start of the year, so I expected a battle today, and it was. I really had to dig deep at the end of the first, and also the second set. But I’m really happy to have the victory.”

Ivanovic maintained controlled aggression throughout the 81-minute affair, striking 26 winners to 22 errors; Gasparyan did her best to stay with the former No.1, but was unable to dictate play in the crucial moments, hitting 16 winners to 18 unforced.

Earlier in the day, hometown favorite Daria Kasatkina overcame a tough three-setter from Kirsten Flipkens, and noted the slowness of the court after her 6-4, 5-7, 6-4 victory. But Ivanovic disagreed.

“I actually really enjoyed it,” said the Serb. “Sometimes the ball really skids so it’s not so slow at times. But I’m really happy with the way I played today, especially being my first match.”

Hoping to catch up on her sightseeing, Ivanovic joked about narrowly missing out on the visiting hours at the Hermitage museum on Tuesday.

“I’m going to train, do my recovery. But I’m going to visit the Hermitage; I went yesterday, but they really, truly closed the door in front of me! I wasn’t lucky but tomorrow might be a better chance.”

Kasatkina had to overcome nerves in her first round match against Flipkens, a 2013 Wimbledon semifinalist; serving for the match at 5-4 in the second set, the 18-year-old admitted nerves played a part in her going on to lose the final three games to force a decider.

“I was nervous, and started rushing, plus Flipkens is a very good player,” she said in her on-court interview.

In the end, Kasatkina played an even match, hitting 34 winners and the same number of erros, while Flipkens was far looser with a -8 differential (32 winners, 40 unforced). A former Roland Garros junior champion, Kasatkina next plays lucky loser Laura Siegemund, who upset No.7 seed Kristina Mladenovic, 1-6, 7-5, 6-1.

Elena Vesnina was another Russian to emerge victorious on Wednesday; the wildcard recovered from a set down to defeat lucky loser Patricia Maria Tig, 3-6, 6-3, 6-1. Dominika Cibulkova set up a second round encounter with former No.1 Caroline Wozniacki when she beat Evgeniya Rodina, 6-0, 6-3, and Annika Beck continued her winning ways from a successful Fed Cup debut when she beat Lucie Hradecka, 4-6, 7-5, 7-5.

No.2 seed Roberta Vinci and Yanina Wickmayer were the last match of the day on Sibur Arena; the 2015 US Open runner-up played a clean match to outsteady the up-and-down Belgian, hitting 17 winners to 10 errors – compared to 22 winners and 30 errors from Wickmayer – to join Ivanovic in the last eight, 6-2, 7-6(2).