Spaniard Ferrer still has a good chance of clinching one of three remaining spots for the season-ending event in London, for which Rafael Nadal, Roger Federer, Novak Djokovic, Andy Murray and Robin Soderling have all qualified.

Fourth-seeded Ferrer, the 2008 champion, did not face a single break point on his serve against Gabashvili, ranked 99, and will play Italian Potito Starace on Friday for a place in the semifinals.

Second seed Soderling booked his place in the last eight when he swept aside Spaniard Daniel Gimeno-Traver 6-2, 6-3.

The Swede was joined by Russian sixth seed Nikolay Davydenko, who survived a tough first set to come through 7-6, 6-2 against Juan Ignacio Chela of Argentina and set up a quarterfinal clash with Frenchman Gilles Simon.

Soderling will play the winner of Thursday's match between Simon's compatriot Gael Monfils and Stanislas Wawrinka of Switzerland.