Oscar Hernandez was born on April 10th, 1978 in Barcelona, Spain. He turned pro in 1998 and has won 9 titles on the Challenger Circuit. His highest ever ranking came in October 2007 when he reached number 48. That year he had his best run in a Grand Slam, the 3rd Round of the French Open.

Hernandez recorded wins over Juan Pablo Guzman and Philipp Kohlschreiber before losing to Jonas Bjorkman. At the US Open he lost to Jo Wilfried Tsonga in the first round and suffered an early exit at Wimbledon losing to Gilles Muller in round one.