Serena Williams knows she will have to step it up another level against fellow American Danielle Collins, according to Chris Evert.
The 23-time Grand Slam champion defeated Mihaela Buzarnescu 6-3, 5-7, 6-1 on Wednesday to move into the third round of the French Open, but Evert thinks her next match could be even tougher.
Speaking in the Eurosport Cube, 18-time Grand Slam champion Chris Evert says Serena can always raise her game in the big moments but she will need to focus more to keep her consistency.
"One thing you can still say about Serena is that she always steps it up a level on the big points," said Evert.
"She hasn't forgotten about the ebbs and flows of a match, when she has to turn it on, when she needs to focus a little more.
"Buzarnescu lost a lot of break points, the big points, because Serena just came on top and she hasn't lost that instinct to play well when there is danger."
Serena had a poor build up to Roland Garros this year, winning only one match on clay at Parma, Italy and crashing out in her first match at Rome, but Evert says her level is impressive.
"Serena is coming back pretty quickly - before this tournament she only had three matches. She's looking better and better, moving smoother on the clay, and she's being patient.
"In the next match against Danielle Collins, look for fireworks because this is a feisty young player, warned Evert.
"Danielle has come on strong, she hits the ball hard and flat and you will feel her presence on court.
"It will match Serena Williams - they are both strong-minded and we could have a clash of the titans in that match. I'm really looking forward to it."
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