Rory McIlroy says golf must improve its drug-testing regime as he could "get away with" doping as it stands.
The most recent report from the World Anti-Doping Agency revealed 507 tests were carried out on golfers in 2014, with eight testing positive.
"I've been tested once this year but it was only a urine test," said the Northern Irish world number four.
"You can't really pick up HGH (human growth hormone) in a urine test, so I could use HGH and get away with it."
The 27-year-old added: "If golf is in the Olympics it needs to improve the drug testing.
"On average, we get tested four or five times a year. It's very little compared to other Olympic sports."
A UK Anti-Doping spokesperson told BBC Sport: "UK Anti-Doping are currently in the process of carrying out a comprehensive testing programme for British athletes heading to the Olympic Games this summer.
"This programme includes golf and players who will form part of TeamGB in Rio this summer."
The International Golf Federation, which is responsible for the testing programme, has not commented.
In 2014, Wada carried out 283,304 tests worldwide, with banned substances found in more than 3,800 samples.
It told BBC Sport more than 10% of elite athletes could be using performance-enhancing drugs.
Golf had the fewest number of tests of all the summer Olympic sports.
Speaking in the build-up to the Open Championship at Royal Troon, McIlroy added: "Drug testing in golf is some way behind the other sports - but I don't think there are drugs that can make you better across the board.
"There are drugs that can make you stronger and make you concentrate more, but not that can make you a better all-round golfer, as far as I am aware."
Last month, McIlroy withdrew from the Olympic Games in Rio because of concerns about the Zika virus.
The Open begins on Thursday, and McIlroy has been grouped with Hideki Matsuyama and Bubba Watson for the first two rounds.
|The Open Championship|
|Venue: Royal Troon, Ayrshire, Scotland Dates: 14 July to 17 July|
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