Probably the most hard working player in the top eight – Sara Errani will be in action today up against the replacement for Czech Petra Kvitova, 2011 US Open champion Samantha Stosur.

Stosur has had to endure a difficult year so far. She lost in the opening rounds at Sydney and then again in Australian Open. In February a much improved Stosur reached the finals of the Qatar Total Open, but lost to Victoria Azarenka. Her form fell once again in March and she disappointed in Miami and Indian Wells. April was another tumultuous month for the Aussie as she continued to crumble. In Stuttgart she lost in the quarters to Maria Sharapova in three sets after holding a match point at 5-3 in set 2. Her clay court season was only salvaged by her Roland Garros run as she reached the semis of the event eventually losing to breakthrough Italian Sara Errani.

At Wimbledon and the Olympics, Stosur struggled to make any form of impact and ended up a losing early in both the tournaments as she struggled to cope with the grass courts. At the US Open, Stosur finally got her act together as she reached the quarter-finals, only to be undone by World No.1 Victoria Azarenka. She is lucky to be here at the championships, but does still have enough to upset any of the big players.

Sara Errani has reinvented herself this season. The Italian is currently ranked as World No. 7 and she has won 4 WTA titles this season. Errani has an impressive - win-loss record for the season so far. The twenty five years Old Italian also reached her maiden Grand Slam final at Roland Garros this season but she failed to win the title.

These two have played each other six times before and Errani has a lone win that came in this year's Roland Garros semifinal.

TennisEarth picks a win for Stosur in this one.