Medvedev was given a code violation in the first set on Saturday (AEST) after snatching a towel from a ball boy's hand. He responded by tossing his racket in the direction of the umpire's chair.

Unseen by the umpire, Medvedev then directed a middle-finger gesture at the crowd, with the fans inside Louis Armstrong Stadium incensed after seeing him do so on the big screen.

Medvedev was jeered throughout the contest and after he wrapped up a four-set victory in the third-round clash.

The 23-year-old Russian seemed to revel in the boos and told the crowd: "The more you do this, the more I will win."

He later said his actions were brought on by the heat of the moment and said: "Hopefully I will do better next time."

Medvedev's fine consisted of two separate amounts for unsportsmanlike conduct and a "visible obscenity".

The world No.5 will look to put the episode behind him when he faces qualifier Dominik Koepfer on Monday (AEST).