Jon Rahm believes the PGA Tour will find it “extremely difficult” to prevent fans who have gambled on golf tournaments from trying to directly affect the outcome.

Two fans were ejected from last week’s BMW Championship for shouting at Max Homa as he took a putt on the 17th green during the third round of the second FedEx Cup play-off event, which boasted a first prize of $3.6m (£2.8m).

The bet was apparently for just three dollars between friends and Homa said afterwards: “It was nice to make it right in the middle and hopefully he had to pay his buddy that three dollars immediately on the way out of the property.”

Roma added: “I love that people can gamble on golf, but that is one thing I’m worried about. It’s just always something that’s on your mind. It’s on us to stay focused or whatever, but it’s just annoying when it happens. … Fans are so great about being quiet when we play. I think they are awesome. When anybody ever talks, it’s so unintentional. They don’t know we’re hitting. It just sucks when it’s incredibly intentional.”

Speaking ahead of the Tour Championship in Atlanta, Rahm said such comments were more common than most people realized.

“I feel like we hear it every single round. That happens way more often than you guys may hear. I mean, it’s very, very present,” the Masters champion said.

“In golf, spectators are very close, and even if they’re not directly talking to you, they’re close enough to where if they say to their buddy, I bet you 10 bucks he’s going to miss it, you hear it.

“Luckily golf fans are pretty good for the most part and you’re hearing the positive, I got 20 bucks you make birdie here, things like that. But no, it’s more often than you think.

“I think the tour maybe should look into it because you don’t want it to get out of hand, right?

“It’s very easy, very, very easy in golf if you want to affect somebody. You’re so close, you can yell at the wrong time, and it’s very easy for that to happen.

“So I think they could look into it, but at the same time, it would be extremely difficult for the tour to somehow control the 50,000 people scattered around the golf course, right?

“So it’s a complicated subject. You don’t want it to get out of control, but you also want to have the fans to have the experience they want to have.”

PGA Tour commissioner Jay Monahan told ESPN.com the incident was “unfortunate”.

“Our fans have great appreciation for the integrity of the competition,” Monahan said. “They’re respectful of our players. We have seen that continue to be the case and expect that to continue to be the case. We have tremendous fans that have tremendous respect for what these players need to do in order to provide and present the tremendous performances they do.”