Watch out for Muchova!

Karolina Muchova is having one hell of a US Open.

Injured for much of the season, the player now down to 52nd in the world is bluffing her way through the world.

Boasting powerful strokes and a formidable serve, the Czech player has just dominated Jasmine Paolini to reach the quarter-finals (6-3, 6-3).

Impressive since the start of the tournament, she goes into the next round without losing a set and could well be the surprise of the tournament.

Last year's semi-finalist in New York, the Czech will be a tough nut to crack.

Her next opponent will be the winner of the duel between Wozniacki and Haddad Maia.