(VIDEO) Cameron Norrie's struggles evident, serves underarm but gets heavily booed at Rio Open

Cameron Norrie was dumped out of the semi finals at the Rio Open on Saturday. The defending champion lost against qualifier Mariano Navone in straight sets.

Norrie appeared to be struggling with the humid conditions and received medical attention at one point during the tie. In an effort to spark himself into life, he attempted an underarm serve whilst trailing 3-5 in the first set at deuce. Norrie's plan did not come to fruition, however, as his Argentine opponent was able to read the play and simply hit a winning forehand. The crowd in the arena were not pleased with this, booing Norrie for his decision.

The underarm serve in tennis has drawn criticism from those in the game, believing it is disrespectful to opponents to try one, but others say it can be a smart way of catching one's opposition off guard, and winning a point in the process.

Norrie will be back in action at the Acapulco Open, where he will take on German Dominik Koepfer in the first round in Mexico.