Serena Williams has been backed by the head of the women's tour after complaining about being forced to play on Court Two at Wimbledon.The defending champion, 29, expressed her feelings after she beat Romanian Simona Halep 3-6 6-2 6-1."Serena is a four-time champion and defending champion at Wimbledon - I share her disappointment," said WTA chief Stacey Allaster.The All England Club denied there was any bias against Williams."There is certainly no intention to favour any player or players," said a statement from the organisation that runs Wimbledon.The seventh seed believes that both herself and her sister Venus, who played on Court Two for her opener, have not been treated in the same way as the men's elite.The top four of Rafael Nadal, Novak Djokovic, Roger Federer and Andy Murray have played their matches exclusively on Centre and Court One so far."Yeah, they're never moved across," said Serena, who will play Russian 26th seed Maria Kirilenko in the third round."Venus and I have won more Wimbledons together than a lot of the players, or by ourselves in doubles even."They like to put us on Court Two, me and Venus, for whatever reason. I haven't figured it out yet. Maybe one day we'll figure it out. I don't know."Serena has recently returned to the tour following a 49-week absence caused by a foot injury and a blood clot. She won her first Wimbledon title in 2002 and has 13 Grand Slam titles in total. She has also won 12 Grand Slam doubles titles with sister Venus.Serena is also only the fifth woman in history to have held all four Grand Slam singles titles simultaneously.Source: BBC