Nadia Petrova tells Sport Express Russia that she doubts that world No. 8 Sara Errani can remain an elite player. The 2012 French Open finalist defeated Petrova last week in Dubai.

“When you are constantly carrying on the court for two or three hours, it eventually affects you,” she said. "Therefore, those who play such boring tennis, mostly relying on errors from their opponents, don’t stay in the elite for a long time. I prefer a different style.”

Petrova also added that Serena Williams is a cut above the rest of the players as well as a “true leader on tour.”

“Serena is such an important figure for our sport,” Petrova said. “There really aren’t that many really outstanding personalities in women's tennis. For example, Agnieszka Radwanska is playing well, but still is not the best. Vika Azarenka, admittedly, not all see her as the leader of our tour. Kvitova, Stosur, Kerber—great players. But Serena is only comparable to Maria Sharapova.”

Petrova said she doesn't see potential greatness in young players, even though she admitted she hasn't seen all the top young players play too much.

“Yulia Putintseva, judging by the improvement in her results, wants to achieve great things,” Petrova said. “There has been average play from Madison Keys and Sloane Stephens. There’s Kristina Mladenovic, but she’s still unstable. No one else comes to mind.”