In October, del Potro beat qualifier Grega Žemlja to win the Erste Bank Open in Vienna. He then beat Roger Federer to win the Swiss Indoors title, in Basel. The following week, he suffered a third-round loss to Michaël Llodra at the BNP Paribas Masters. During the round-robin stage of the ATP World Tour Finals, he won two of his three matches and qualified for the semifinals, where he was defeated by Djokovic in three sets, after leading by a set and a break.