It’s not as easy out there as they make it look, and professional golfers are not always as calm as they appear to be.

Just ask So Yeon Ryu.

Whenever she approaches a putt, she is the picture of confidence. And if the ball doesn’t go into the hole, she rarely displays a negative reaction.

Ryu is among four golfers who finished Thursday’s second round of the Lotte Championship at 11 under par. Usually — especially when conditions are less than perfect — that’s a score good enough to be in the lead or very close to it midway through the event.

But Ryu, Nelly Korda, Hyo Joo Kim and Luna Sobron Galmes have a very tough challenge ahead of them.

Yuka Saso at 16 under and Lydia Ko at 14 under are threatening to run away from the rest of the field. That is despite the wind, and despite the general unfamiliarity with the course; this tournament is normally played a couple of miles away at Ko Olina Golf Club. Some of the players — including Saso — weren’t even alive the last time the LPGA played a tournament at Kapolei, in 2001.

“Even though I shot 11 under for two days, it’s actually not easy conditions,” said Ryu, whose 4-under 68 on Thursday was tied for the 19th best round of the day. “I really don’t know how so many players are playing so well.”

Ryu started out fine, with two birdies on her first two holes, and she was 3 under for the day at the turn. Then, on the front nine (she played the back nine first). Ryu hit the greens, but sank just one birdie putt. She said they were not gimmes, even for a former LPGA rookie of the year, player of the year and two-time major winner like her.

“It was so windy out there. Like it was really hard to judge,” she said. “Also, like to be honest, like the back nine I didn’t really have much birdie chances. I don’t think I had many putts like within 15 feet. If it’s outside of 15 feet I would say even though that’s a birdie chance, it’s not really a birdie chance.”

As for nerves …

“I think every golfer is pretty much a great actress,” Ryu said. “We are nervous all the time. Even, for sure, Inbee (Park) looks calm all the time, but she gets nervous, too.”

Ryu said she felt nervous before yesterday’s second round like she normally would before a final round.

“So I really tried hard to calm myself down, and I think I did it really well,” she said.

The birdie-birdie start verified that.

“Nerves are not always a bad thing,” she said. “Like, you have to have that to bring out your A game. Having a great amount of nerve has always helped me play better golf. So I hope I can manage that level really well for the next two days.”

And she knows not to worry about anyone else’s score at this point.

“Somehow I was able to manage pretty well to shoot 11 under,” Ryu said. “If I can do that again the next two days it’s going to be 22 under par, and whether it’s going to bring me the trophy or not I think I’m going to be happy.”