Juan Martin del Potro reached the final of the ATP World Tour Finals after squeezing past Swede Robin Soderling 6-7 6-3 7-6 to set up a showdown with Nikolay Davydenko in London. The Argentine looked to be on his way out when Soderling broke him for a 4-2 lead in the third set but the Argentine world number five hung in to eventually prevail 7-3 in the tie-break, firing down his 12th ace.