[ATP World Tour Final, Sat] del Potro’s upset win over Federer means he goes to semis and Ferrer goes home
Federer had been hoping to get back on the winning track beating del Potro. Ever since del Potro returned to tour after nearly a year off from playing, he has slowly, but surely been ascending up the ranks. Federer has, in the meantime, been able to beat del Potro on a regular basis, biding his