However, on 22 July, the USTA stated that del Potro was expected to defend his US Open crown. The player himself confirmed that his comeback to the tour would be the Thailand Open and said nothing about the New York event. On 2 August, del Potro returned to the practice courts. A week before the start of the US Open, after practicing for two weeks, del Potro withdrew from the event, as he felt he was not ready to compete at the highest level. After the nine-month break, del Potro confirmed that he would make his return at the 2010 PTT Thailand Open. In his return match, he lost in the first round to Olivier Rochus. He then also played at the 2010 Rakuten Japan Open Tennis Championships, but again lost in the opening round, this time to Feliciano López. 2011: Return to tour, second Davis Cup final Del Potro began his 2011 season at the Medibank International as a wildcard entry. In the second round, del Potro was defeated by Florian Mayer of Germany in straight sets, despite winning against sixth seed Feliciano López in three sets in the first round. His next tournament would be the first Grand Slam of the year at the 2011 Australian Open, where del Potro was defeated by 21st seed Marcos Baghdatis in the second round. As a result, del Potro slipped further down the rankings to No. 485. After the Australian Open, he participated in the 2011 SAP Open in San Jose, where he was accepted into the main draw via protected ranking (PR). He reached the semifinals without dropping a set, however he lost to top seed Fernando Verdasco in straight sets. Del Potro's next scheduled tournament was the 2011 Regions Morgan Keegan Championships and the Cellular South Cup, where he was accepted into the main draw via wildcard. Here, he made his second consecutive ATP semifinal, where he lost to top seed, world No. 8, and eventual champion Andy Roddick. To continue preparing for his first ATP Masters event since 2009, del Potro entered the 2011 Delray Beach International Tennis Championships. He defeated Ričardas Berankis, Teymuraz Gabashvili, Kevin Anderson and second seed Mardy Fish, to advance to an ATP-level final stage of a tournament since 2009 at the Barclays World Tour Finals in London. In the final, he defeated an erratic Janko Tipsarević in two sets to get back in