Defending champion Richard Gasquet and world number six Tomas Berdych will attempt to make the most of Andy Murray\'s absence from this week\'s Thailand Open as the battle to reach the season-ending Tour finale heats up. The withdrawal of the Wimbledon champion, who undergoes back surgery on Monday, is a major blow for tournament organisers but a golden opportunity for a clutch of players seeking points to reach November\'s ATP World Tour Finals in London. Czech player Berdych is fifth in the race to London -- which features the season\'s top eight players -- while Gasquet is in ninth place. Canada\'s Milos Raonic is also in the mix as the tour starts its Asian swing. In the course of a breakneck few weeks, there are also events in Kuala Lumpur, Tokyo, Beijing and Shanghai, before the players return to Europe for the final stages of the season. Frenchman Gasquet, 27, returns to Bangkok where he lifted the trophy in 2012, sweeping aside compatriot Gilles Simon in the final. The second seed will hope to carry the momentum to Thailand from a run to the US Open semi-finals, where he lost to eventual champion Rafael Nadal. Raonic, ranked 11, who reached the quarters in Bangkok last year, will be hoping Murray\'s absence opens the way for a genuine title shot to add to his solitary singles win this season in San Jose. The Canadian third seed changed coaches in the spring, taking on Croatia\'s former top-five player Ivan Ljubicic, who has urged his new charge to improve his all-round game, which is often overly reliant on his ferocious serve. Since making the change, Raonic has made the final of the Montreal Masters, reached the second week of the US Open and this month played a major role in unfancied Canada\'s narrow Davis Cup semi-final loss to Serbia. \"I think I\'ve improved a lot of things, I\'m playing quite a different way,\" said the 22-year-old. \"That\'s the way I need to keep playing if I want to achieve what I want to achieve.\" Fresh from helping his country swat away Argentina in the Davis Cup semi-finals, Berdych, 28, is playing in Bangkok for the first time since 2008, when he lost a semi-final to Novak Djokovic. He arrives as the highest-ranked player and top seed. The top four seeds all receive byes into the second round. Source: AFP