Chakvetadze rounds out

The seventh seeded Russian won thanks to a stunning turn-around after dropping seven straight games to go down a break in the third and final set.

Chakvetadze advances in the second place out of the yellow group behind group winner Justine Henin, and will face either Serbia's Ana Ivanovic or compatriot Maria Sharapova in the last four.

A semi-finalist at this year's US Open, Chakvetadze finishes her best year on the WTA Tour on a high with her second victory this year over the world number three.

The 20-year-old started the match brilliantly breaking the third seeded Serbian in the fourth game, but Jankovic matched the Russian with her own break of serve in the next.

The opener appeared headed for a tie-break after Chakvetadze concluded the first love-service game of the match with an ace to go ahead 5-4, but the Russian broke Jankovic in the very next game thanks to a pair of excellent backhands.

The Serbian, who had won the most matches on the WTA Tour this year, then started the second set with a break of serve that was a harbinger of things to come as Jankovic won the seven straight games to bagel the Russian in the second and go up a break in the third.

Chakvetadze responded beautifully though, after being handed the break back on a platter thanks to a Jankovic double fault on break point.

The 22-year-old Serbian number one finished the night with eight double faults to Chakvetadze's six, as errors clearly cost her despite some excellent defensive play during all three sets.

Chakvetadze broke to love with a gorgeous backhand winner down the line to win her fourth game in a row and go up a double break at 3-1 in the third set.

Jankovic finally held serve again in the sixth game of the set, but by then it was too late as Chakvetadze served out to claim the victory in one hour and 37 minutes and collect the last semi-final berth in the Spanish capital.