CNN  — 

Apart from the thwack of club on ball and muted conversations between players as they wander from fairway to green, the sound of golf for much of 2020 has been missing one key ingredient – the roar of fans.

So, after competing for so long without spectators lining the holes at courses because of the coronavirus pandemic, it was a welcome sight for players to a limited number of fans cheering them on.

The Houston Open, which began on Thursday, is the first PGA Tour event in the US to have fans on-site since March. Two thousand tickets were sold for each round of the tournament.

And having people walking the course alongside them did cause some experienced players to double-take.

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Fans, wearing masks, watch action on the ninth green during the first round of the Houston Open.

“There’s people walking around and I was like: ‘What’s going on?’” American golfer Adam Long said after shooting 68 on Thursday.

“Completely forgot. It’s nice. It gets you excited a little bit, gets you fired up. It’s nice to hear some claps out here when you’re fortunate enough to hit a good shot.”

And although it wasn’t the first PGA Tour event to have fans in attendance – last week, 500 fans per day were permitted at the Bermuda Championship – it was the first on US soil.

“It’s great having fans back out again,” Scottie Scheffler said after shooting 67 on Thursday in his opening round. “The energy was definitely a lot different than us just being out here by ourselves.”

Fans look on during the first round of the Houston Open.

“I think the PGA Tour’s done a great job keeping us safe and keeping the fans safe. I think it’s great that they have the freedom to come out here and watch. Pretty much everyone was wearing a mask that I saw, so I felt very safe out there on the course.”

Brandt Snedeker birdied two of his final four holes to grab the lead after day one at the Houston Open.

The American shot a five-under 65 to take a two-stroke lead in the last event before the Masters starts November 12. He’s one of 37 players in the field this week set to play at Augusta National.

“I love having fans out here, I kind of feed off their energy,” the 39-year-old said after setting his first-round lead. “It’s great to hear some claps and people excited for good shots and some birdies.”

However, the last tune-up event before The Masters didn’t go to plan for some of golf’s biggest names.

Johnson and Spieth talk together on the putting green ahead of the Houston Open.

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World No. 1 Dustin Johnson – making his return after his positive Covid-19 test – shot a 72, bogeying five of his last seven holes on his front nine, while four-time major winner Brooks Koepka also shot a two-over 72.

Jordan Spieth finished three-over after the first round while Phil Mickelson had two double bogeys and two bogeys as he shot an opening round 76.