Verdasco through in Valencia 

Source: ReutersFernando Verdasco of Spain

Fourth seed Fernando Verdasco advanced to the second round of the Valencia Open on Thursday after Spanish compatriot Oscar Hernandez retired with back trouble.

A dominant Verdasco was leading 6-1 0-1 when Hernandez called it a day.

World number eight Verdasco is one of six players at the Spanish indoor hardcourt tournament chasing the two remaining spots at the season-ending World Tour Finals in London.

Roger Federer, Rafael Nadal, Novak Djokovic, Andy Murray, Juan Martin del Potro and Andy Roddick have all qualified for the Nov. 22-29 event and Valencia second seed Nikolay Davydenko and Verdasco currently occupy the remaining two places.

Verdasco will play Janko Tipsarevic in the second round in Valencia after the Serb defeated Victor Hanescu 6-4 6-3.

Frenchman Jo-Wilfried Tsonga's hopes of making the cut for London suffered a setback when a left wrist injury forced the third seed to retire from his first-round match. He was trailing Mikhail Youzhny 6-7 6-0 3-0.

Tsonga's compatriot Gilles Simon, who also eyeing place in the Tour Finals, battled past Czech Tomas Berdych in the second round 6-4 4-6 6-3.

Gael Monfils, another Frenchman, had his hopes of a place in London squashed by Guillermo Garcia-Lopez, the Spaniard winning 6-2 7-5.

On Friday, top-seeded Briton Murray plays Leonardo Mayer of Argentina.