Coric stuns Isner, Bautista Agut eases through

Croatian Borna Coric

Borna Coric stunned John Isner to reach the Winston-Salem Open quarter-finals, while Roberto Bautista Agut eased through.

Coric inflicted what was the in-form Isner's first ever defeat at the ATP 250 event, claiming a 7-5 6-2 victory in their third-round clash on Wednesday.

The Croatian managed to break the Isner serve three times, the American – winner of titles in Newport and Atlanta recently – bowing out in his home state of North Carolina.

Awaiting Coric in the last eight is Jan-Lennard Struff, who battled past Andreas Seppi 6-3 6-7 (3-7) 7-6 (7-3).

Big serving and great returning from @borna_coric as he moves into the QF of #USOpenSeries @WSOpen with a 7-5, 6-2 victory over Isner. pic.twitter.com/e984q3xLkv

— US Open Tennis (@usopen) August 24, 2017

Bautista Agut, the top seed and last year's runner-up, cruised through, beating Marcos Baghdatis 6-3 6-4.

A forehand winner does the trick as @BautistaAgut powers into the #USOpenSeries @WSOpen QF with a 6-3, 6-4 win over Baghdatis! pic.twitter.com/sH2a6Fl94r

— US Open Tennis (@usopen) August 23, 2017

Next up for the Spaniard is Taylor Fritz after the American teenager edged Paolo Lorenzi 7-6 (7-3) 7-6 (7-5).

On the other side of the draw, seeds Steve Johnson and Chung Hyeon progressed.

Johnson, the sixth seed, was too good for Carlos Berlocq 7-6 (7-1) 6-4 and next faces Kyle Edmund after the Brit beat fellow qualifier Marton Fucsovics 6-2 6-1.

Chung led Julien Benneteau 6-4 1-1 when the French 2011 runner-up retired, with Damir Dzumhur awaiting the South Korean after the Bosnian's 7-5 6-3 success against Horacio Zeballos.