Former world number one Jelena Jankovic enjoyed a successful summer last year winning the title in Cincinnati after getting past some of the biggest names. The 2010 season also started on a good note when she claimed the title at Indian Wells. The second hardcourt season of the year though seems like a tough road for the Serbian as she injured her left ankle during her second round match at the Banka Koper Slovenia Open being played here in Portoroz, Slovenia.

Jankovic won the opening set easily but saw a shift in momentum when her opponent, Belarusian qualifier Anastasia Yakimova levelled the match by winning the second 6-3. As the decider began, Jankovic felt excruciating pain and decided to sit by the sidelines after trailing by a game.

Yakimova now faces Russian Ksenia Pervak, who edged past compatriot Alexandra Panova 6-2, 7-5.

Meanwhile third seed, Anastasia Pavlyuchenkova also made the cut to the quarterfinals with a straight sets drubbing of Spaniard Rossana De Los Rios, winning 6-3, 6-0 in just 67 minutes of play.

I'm happy with my performances so far here," said Pavlyuchenkova. I came here to do my best and play well, so we'll see how things go the rest of the tournament."

Pavlyuchenkova's opponent in the last eight is the young Swede Johanna Larsson, who took out Italian Maria Elena Camerin 7-5, 6-1 in a one hour 39 minute match.