Should golf drug test more? Rory McIlroy says so.

The world's fourth best golfer said he thinks he should be blood-tested to ensure the integrity of the sport.

As other Olympic sports grapple with their own doping scandals, the world’s fourth best golfer sounded off Tuesday about what he sees as the sport’s lax drug testing.

"I've been tested by the IGF [International Golf Federation] once this year ... but it was only a urine test. I haven't been blood tested yet. I, on average, probably get tested four to five times a year which is very little compared to the rest of the Olympic sports," said Rory McIlroy, at a news conference ahead of the 145th British Open in Scotland. “Blood-testing needs to happen in golf just to make sure it is a clean sport going forward.”

Mr. McIlroy’s criticism not only raises questions about a culture of performance-enhancing drugs in yet another sport, but also shows how a player can push forward a conversation about changing it, especially if officials won’t.

Roger Pielke, a professor at the University of Colorado who specializes in the governance of sports organizations, and has been critical of the World Anti-Doping Agency (WADA), said it's best for reforms to come from athletes themselves.   

"The players have a voice," Mr. Pielke told Golf Magazine in January. "If there's evidence that there's a doping problem on the PGA [Professional Golfers Association] Tour that the players want to address, let's open up a conversation with the athletes about what actions might be needed."

It appears McIlroy has done just that, questioning Tuesday why golfers do not receive blood tests.

The PGA started its drug-testing program in 2008, conducting urine tests at tournaments. Since then, it has suspended three players. The first was Doug Barron in 2009. He tested positive for high levels of testosterone. Bhavik Patel and Scott Stallings were each suspended in 2015.

Even some of golf’s most famous names have been pulled into the conversation. Vijay Singh admitted to Sports Illustrated in 2013 he used deer-antler spray. The substance was not explicitly banned by the PGA, but contains the growth hormone IGF-1, which was. Singh was suspended for 90 days. But the Tour lifted the suspension when WADA determined deer-antler spray did not contain enough hormones to improve performance.

Rumors have circulated about Tiger Woods’s use of performance-enhancing drugs. In 2010, a survey by Sports Illustrated found 24 percent of professional golfers suspected Mr. Woods used them.

Amid this criticism, why doesn’t golf perform more blood tests?

Andy Levinson, the PGA’s vice president of tournament administration and anti-doping, has resisted blood-testing players because, he has said, it could harm a golfer’s performance.  

At least one former WADA official disagrees. Dick Pound, the former WADA president who highlighted the corruption of Russian athletics, told The Scotsman in April that golf shouldn’t turn a blind eye to the improved performance and build of its athletes.

“If you follow some of the shape changes in the golfers and follow how, at a certain point, if they happen to come off them, you see how many more injuries they get,” said Mr. Pound. “There’s a problem there.”

Other athletes have sounded the alarm about doping scandals in their respective sports. One of the most notable instances of late were allegations against Russia’s state-sponsored program brought forward by Russian runner Yuliya Stepanova. US distance runner Kara Goucher and her husband, Adam, publicly alleged unethical practices in the training group of her coach, Alberto Salazar, backed by global sports icon Nike.

Russia's track and field team was barred from this year’s Olympics, while the investigation into Ms. Goucher’s claims is ongoing.