Stoner remained with Ducati for the 2009 season with new teammate Nicky Hayden, with a further option for a 4th season in 2010. A strong start to the season left Stoner in a three-way battle with the Fiat Yamaha duo of Rossi and Jorge Lorenzo, before he was struck by a mystery illness which caused him to feel tired long before the end of races, leaving him 16 points behind Rossi and 7 behind Lorenzo after the US Grand Prix at Laguna Seca on 5 July.