Once Japan’s Rikuya Hoshino calmed his nerves to lace the opening drive down the fairway shortly after 7:30am local time, focus turned to his fellow playing competitors, Sepp Straka of Austria and Thomas Pieters of Belgium, as they made quick work of the ideal scoring conditions. Quite literally.

By the time Straka set an East Course record and matched the 2016 Olympic men’s record of 8-under-par 63, and Pieters shot his own 65, they were nearly three full holes ahead of the next grouping. Straka’s two-stroke lead eventually would dwindle to one after Jazz Janewattananond of Thailand, who was 6-under through 15 when an afternoon thunderstorm delayed play for over two hours, came back to birdie the final hole for a 64.

“We didn't have to wait on anybody, and we played quickly, but we didn't feel rushed because we had some pretty good space between us and the group behind us, so that was really key.” - Sepp Straka.

Pieters, who overcame a rough day on Wednesday with a slight fever and headache, was matched by Carlos Ortiz of Mexico, while Joachim Hansen of Denmark and Jhonattan Vegas of Venezuela shot 66. The top of the leaderboard was decidedly international, with 17 countries represented among the top 20, which excluded notable names such as the host country’s main hope, Hideki Matsuyama (69), Collin Morikawa (69) and Justin Thomas (71 with 18 pars) of USA, and Rory McIlroy of Ireland (69), to name a few.

Straka, who lived in Austria until age 14 before his family moved to the U.S., obviously was comfortable in the lead-off position and with the pairing he had.

“We had a really good group, had some good mojo going in the group and first off was great,” he said. “We didn't have to wait on anybody, and we played quickly, but we didn't feel rushed because we had some pretty good space between us and the group behind us, so that was really key.”

On the surface, Straka seemingly had no reason to expect a round that matched the 63s recorded at the 2016 Rio Olympics by Australia’s Marcus Frazier (first round) and bronze medallist Matt Kuchar of the USA (final round). In his last seven starts on the PGA Tour, Straka had six missed cuts sandwiched around one bright spot of a T10 at the Travelers Championship. But he saw promise.

“I felt like my game was in a pretty good spot,” said Straka, who has the added support this week of twin brother Sam serving as his caddie. “Those first few weeks before Travelers when I missed the cut my irons were bad, but my short game was really good. So, I worked on my irons a lot and then my short game got bad. So that's when I missed the last couple cuts. But yeah, I just changed my putting routine up a little bit and it worked really well, and my irons have been pretty good the last few weeks, so I felt pretty good about my game.”

Straka was steady throughout, giving himself good scoring opportunities with fairways hit and strong iron play to finish with eight birdies.

Janewattananond, meanwhile, checked his initial nerves to finish the day with an unblemished card that included seven birdies.

“I feel very good to be representing Thailand,” he said. “Playing golf is a different mindset when you’re not playing for yourself, but you’re playing for your country and a medal. I’ve played every major. I got very nervous at the Masters, but this was more nervous than that.”

Pieters, on the other hand, didn’t know what to expect as he entered the day, physically drained from the fever and headache that still had a lingering effect when he woke up Thursday.

“I felt horrible this morning even when I woke up, but maybe it's just because I wasn't thinking about bad shots or places not to hit it,” he said. “My caddie (Adam Marrow) told me hit it there and I did it … I kept it simple.”

Pieters was only able to practice on the front nine, which he played Thursday in one under par. Then he made the turn and relying on his caddie, holed out for an eagle-2 on No. 11 and added birdies on 13, 17 and 18.

“Adam did a great job,” Pieters said. “I didn’t play my way out of the tournament the first day, so that's good.”

Which leaves him in a position to contend again for a medal. Pieters is the highest returning finisher from Rio, where he finished fourth despite a third-round 77 that sidetracked his otherwise stellar play with rounds of 67, 66 and 65.

Ortiz, who also finished his round before the storm hit, made seven birdies and a lone bogey on No. 9.

“It's a great round, I'm really happy the way I played,” he said. “Everything wasn't perfect from the beginning, I had to figure it out a little bit. I couldn't hit the fairways and this golf course is pretty tough from the rough. So, once I got in a rhythm and started hitting fairways it became a little bit more easy and opened up the golf course. And obviously you guys have seen these greens are perfect, so if you start to roll the ball great you can make a lot of putts.”

It's something that translates easily into all golf languages.