MADRID -- Rafael Nadal's return to competition has been delayed by a stomach virus. The Spaniard was scheduled to play in an exhibition tournament in Abu Dhabi on Thursday after missing seven months because of tendinitis in his left knee. But he said on his Facebook page Tuesday that his doctors ordered him to pull out when he was running a fever, telling him his body needed rest. "My rehab has gone well, my knee feels good and I was looking forward to competing," he said. The 11-time Grand Slam champion hasn't played since June, when he lost to 100th-ranked Lukas Rosol in the second round at Wimbledon. The injury prevented Nadal from defending his Olympic singles gold at the Olympics in London, where he was supposed to be Spain's flag bearer at the opening ceremony.