Juan Martin del Potro must rouse himself for another physical and mental effort as he prepares to take on Rafael Nadal in the semi-finals of the US Open tonight.

Denis Shapovalov's US Open adventure ended in the fourth round with defeat by Pablo Carreno Busta.

Roger Federer will take on fellow Swiss Stan Wawrinka for the BNP Paribas Open title after both secured straight-sets wins in their semi-finals at Indian Wells.