Andy Murray exhumes confidence to defend the title he won in London four years ago

Britain's Andy Murray serves the ball during a training session at the Olympic Tennis Center in Rio de Janeiro on August 2, 2016, ahead of the Rio 2016 Olympic Games. / AFP PHOTO / ROBERTO SCHMIDT

Adjusting quickly to the Olympic atmosphere and its unfamiliar environment will be key for Andy Murray as he bids to defend the title he won in London four years ago, the world number two has said.

The Scot, who beat Novak Djokovic and Roger Federer en route to gold in 2012, is representing Britain in the men's singles in Rio and will also partner his brother Jamie in the men's doubles.

"Here it's totally different conditions, different venue, different country, so I'll try and treat it like any other tournament and prepare as best I can," he told reporters.

"I remember when I was in Beijing (in 2008), the whole atmosphere surrounding an Olympics is different because you're around loads of the best athletes in the world.

"It was just nice being surrounded by the best athletes from your country, seeing them coming back with medals, it feels a lot more like a team environment."

Half of the men's top 10 will miss this month's Olympics. World number four Stan Wawrinka pulled out with an injury on Tuesday, joining his Switzerland team mate Federer in sitting out the Games.

Other notable absentees include Canadian Milos Raonic and Czech Republic's Tomas Berdych, who withdrew citing concerns over the Zika virus, and Austrian Dominic Thiem, who has decided to focus on the ATP Tour.

Murray, however, said the competition would still be fierce.

"It's still a pretty strong field, a lot of the top-20 players are here even if unfortunately there's a few of the top 10 missing," the 29-year-old added.

The tennis competition at the Rio Games takes place from Aug. 6-14.