“I think my putter went really well today,” said Thitikul, who is yet to win a major.

“In the front nine we had a lot of breeze going and more than the back nine, but [I made putts at] seven, eight, nine which boost the confidence up making the turn to the back nine.

“I really told myself just be patient and focused on the next shot, because [in the] majors you [are] going to miss anyway. What a way to bounce back. It’s more important.”

The event is taking place at the Fields Ranch East course in Texas, with Lee and Korda citing the heat as a factor to contend with.

“I just kept telling my caddie, can you give me another water, can you give me another water,” Lee said.

“I don’t think we could have enough [water] out there. It’s really hot.”

Korda added: “It’s hot; I’m still cooling down right now.

“I’m pretty happy with my first round in the conditions. It definitely takes a toll on you, the Texas heat.”