Daniil Medvedev marches on against Wolf

Daniil Medvedev moved into the fourth round of the US Open with a straight-sets win over JJ Wolf of the USA, 6-3, 6-3, 6-2.

The Russian had his serve broken by the wildcard - the first time it had happened to him this week - but was not thrown off course.

Medvedev, runner-up at Flushing Meadows last year, won the first break point in the second set after a pair of unforced errors from his opponent and appeared totally in control as he fired off eight aces, including one to close out the set.

Wolf matched the hard-hitting Russian's power but a flurry of unforced errors - 41 in the match compared to 10 from Medvedev - proved his undoing.

Back-to-back double faults in the first game of the third set saw a frustrated Wolf kick a tennis ball into the empty stands inside Arthur Ashe Stadium.

Medvedev closed out the campaign with four straight points, and plays either Marton Fucsovics or Frances Tiafoe in the next round.