After a great start on Thursday, Paula Reto had to grind her way to a one-over-par 73 in the first round of the KPMG Women’s PGA Championship at Fields Ranch East at PGA Frisco in Frisco, Texas.

As to be expected in a major championship, scoring was at a premium, and Reto found herself in a share of 26th. She was five strokes off the lead, which was held by Jeeno Thitikul of Thailand at four-under-par. In second was Minjee Lee of Australia on three-under, and there were four players on two-under. Nine players were on one-under, bringing the total of players under par after the first round to 15.

Reto had three birdies under her belt by the time she reached the fifth hole, but the course bit back as she made bogey-double-bogey in the next three holes. Thereafter, it was a case of hanging on for dear life as she made a birdie and a bogey on the homeward nine.

The 22-year-old Thitikul made four pars on the first four holes before posting a frustrating double-bogey on the par-four fifth hole to drop to two-over. It was an early mistake that could have set the tone for the rest of the five-time LPGA Tour winner’s round, one that could have thrown her off for the rest of day one of the year’s third major championship. But Thitikul isn’t like most athletes.

She steadied herself with a par on six before rattling off three consecutive birdies on the seventh, eighth and ninth holes to get back to one-under for the day and turn in 36. Thitikul then picked up a pair of back-to-back birdies on holes 11 and 12 to climb to three-under and ultimately landed one last birdie on the par-three 17th hole to polish off a four-under 68, a strong start to her fourth appearance in this major tournament.

Ashleigh Buhai opened with a three-over 75 for a share of 58th.