Rafael Nadal remains the favourite to win the US Open and move within one on Roger Federer’s tally of 20 Grand Slams after a hard-fought quarter-final win over Diego Schwartzman.

Spanish second seed Nadal won 6-4 7-5 6-2 against the Argentine 20th seed.

But he was made to work as Schwartzman twice rallied from four-game deficits in a stuffy Arthur Ashe stadium.

Nadal, 33, will next play Italy’s 24th seed Matteo Berrettini, who beat Gael Monfils in their last eight clash.

Three of the men’s semi-finalists – Berrettini, Grigor Dimitrov and Daniil Medvedev – have never played in a Grand Slam final.