VIDEO: Marin Cilic takes out frustration on racket during third round match

The reigning US Open champion Marin Cilic has looked miserable through the first two sets of Friday's third-round matchup with Mikhail Kukushkin.

Where once his first serve was his strong suit, Friday, it was his weakness, as the upstart Kukushkin took an early 7-6 (7), 5-3 lead on the 26-year-old Croatian.

Related - VIDEO: CoCo Vandeweghe destroys racket in Round 2 of US Open

Continuing the trend of players venting their anger like American Coco Vandeweghe did days before, Cilic slams his racket into the hard court surface following a dismal opening stanza.