Rafael Nadal and Roger Federer made stunning starts to the Shanghai Masters on Wednesday with comfortable straight-set victories.

It only took the Spaniard 53 minutes to progress against Jared Donaldson, which was two minutes shorter than Federer's first set against Diego Schwartzman.

Alexander Zverev – who, like Nadal and Federer, has already confirmed his ATP World Tour Finals place – had a brief encounter with Aljaz Bedene in his second-round match.

The pair were only on the court 12 minutes before Bedene was forced to retire with a knee injury, third seed Zverev having taken the opening four games.

Kevin Anderson, David Goffin and Dominic Thiem were surprise casualties, but there were no such problems for John Isner.

EASY FOR LAVER CUP TEAM-MATES

During the recent Laver Cup Nadal and Federer paired up for the first time to win a doubles match, and the victories keep on coming for the two men.

Nadal was rarely troubled by Donaldson as he racked up a 13th win in a row, the world number one moving onto a match with Fabio Fognini thanks to a 6-2 6-1 victory.

Schwartzman put up a valiant battle against second seed Federer, but the class of the Swiss shone through, his groundstrokes unerringly accurate – much to the frustration of his opponent.

Two sublime aces completed a 7-6 (7-4) 6-4 victory and booked a third-round clash with Alexandr Dolgopolov.

DIMITROV SURVIVES TRIPLE SCARE

Grigor Dimitrov had a much tougher day against Ryan Harrison as the American came close to causing an upset in the third-set tie-break.

Harrison raced into a 6-3 lead in the breaker to get three match points, but he spurned them all – the final one with a long volley – and Dimitrov made him pay.

The sixth seed picked up four points in a row to move in sight, and he made no mistake with a pinpoint ace, his 16th of the match, securing a 3-6 6-3 7-6 (8-6) win.

Dimitrov will meet Sam Querrey in round three, but fellow seeds Kevin Anderson and David Goffin could not follow suit.

ISNER SURVIVES BUT SEEDS SLIP

While the majority of the seeds in action on Wednesday enjoyed a safe progression to round three, Anderson and Goffin made early exits.

Anderson was a surprise casualty at the hands of Jan-Lennard Struff, while Goffin suffered a 7-6 (7-4) 6-3 defeat to Gilles Simon.

Thiem managed to force a decider after letting the first set slip to Viktor Troicki. The fifth seed managed to draw level from 5-2 down in a tie-break but dropped serve to give Troicki match point and the 31-year-old duly clinched a 6-3 3-6 7-6 (7-5) triumph.

There were no such problems for John Isner, though, as he had the better of two tie-breaks to beat Greek qualifier Stefanos Tsitsipas.