San Francisco Frontiers - Furious Medvedev knocked out by Khachanov in Monte Carlo

Medvedev was hit with a point penalty to start the final game after berating chair umpire Carlos Bernardes and then became embroiled in a heated discussion with the tournament supervisor.

The world number four had already been warned after hurling his racquet when he double-faulted to lose his service game and leave Khachanov a game away from victory.

Medvedev, who took issue with two line calls in his second-round win on Wednesday, felt aggrieved a Khachanov forehand was not called out during a rally that resulted in the latter earning two break points at 5-5.

The arrival of the physio to treat an apparent bleed at the ensuing changeover tipped Medvedev over the edge, with the Russian yelling "Did I call the physio!" at the umpire.

The 28-year-old Russian then demanded of the supervisor "who will take responsibility?" for the decisions.

Television replays appeared to show the shot in question from Khachanov had landed wide of the court.

"It's second day in a row. Guys, open your eyes. Do something. It's out," raged Medvedev.

"The mark is out. They don't know how to referee anymore. Who will take action?

"Yesterday the ball is out, it's called in. Who will take action. This ball is out there. Who will take responsibility?"

Khachanov and Medvedev traded breaks in the first four games of the match before the former landed the crucial blow at 4-3 en route to taking the opening set.

The second set followed serve and Khachanov saved a set point down 5-4 before Medvedev imploded in the next game, losing both his serve and temper, and eventually the match.

Khachanov's reward is a quarter-final Friday against Alexander Zverev or Stefanos Tsitsipas.

B.Johnson--SFF