Del Potro started his 2010 season at the AAMI Kooyong Classic in Melbourne, Australia with a win over Croatian world No. 24 Ivan Ljubičić. On 11 January, he moved up to a career high world No. 4. He was scheduled to face Frenchman Jo-Wilfried Tsonga on day 2 of the Kooyong Classic exhibition tournament, but withdrew due to a wrist injury. He came into the 2010 Australian Open with the injury not healed, and took a month off after the event. In the fourth round, he fell to eventual semifinalist Marin Čilić.