Victorious at Hazeltine in 2019, Green made a promising start at Congressional Country Club to sit in a tie for sixth through the first round, the only Aussie to end the day in red numbers.

Sydney’s Stephanie Kyriacou continued her recent turnaround in form to post an even-par 72 to be tied for 15th while pre-tournament favourite Minjee Lee had three bogeys and two birdies in her round of one-over 73.

It was a similar looking scorecard for Sarah Kemp in her round of 73 with Katherine Kirk (74) and Su Oh (75) all within reach of the cut-line heading into the second round on Friday.

But the entire field sits a distant second to two-time major champion Chun who set a new course record eight-under 64 at Congressional Country Club’s Blue Course to establish a five-stroke lead from fellow Korean Hye-Jin Choi (69) and Thailand’s Pornanong Phatlum (69).

Green is one of nine players in a share of sixth at one-under and was in awe of Chun’s round in wet conditions.

“I don’t know what golf course she’s playing,” Green said.

“We were looking at the scores, and we were, like, ‘Oh, wow, OK, five-under par.’ But still tough on the back nine and to hear that she’s 8, I’m, like, ‘Wow, that’s impressive.’

“That’s like shooting 10-under out here.”

Playing in the morning rain, Green began her championship with a dropped shot at the par-4 first but hit back with birdies at three and six as the weather began to ease.

The softer conditions meant that the course played long and gave even the longer hitters such as Green long irons and hybrids in, the West Australian more than happy to end the day under par courtesy of birdies at 16 and 17.

“It definitely helps the momentum going into tomorrow,” Green said of her late birdie surge.

“The putts that I holed in 16 and 17, they were two similar breaking putts, so it was nice to be able to visualise it and actually go in.

“Even par is a great score out here today.

“Nasa (Hataoka) and I played really well, and it was just like we were kind of feeding off each other and trying to hang in there.

“I knew there were a couple of shorter holes on the back nine that I could kind of access, so I wanted to make sure I wasn’t putting too much pressure on myself. But I wanted to make sure I was putting myself in a position to have a birdie or have a low score.

“After the start I’m just glad that I held in there and stayed patient.”

A four-stroke winner at the US Women’s Open at Pine Needles, Lee entered the championship as one of the most fancied chances.

The 26-year-old dropped a shot at her third hole – the par-4 12th – but made the turn in even par with a birdie at 15 courtesy of a brilliant approach that was one roll from being an eagle.

A bogey at two and birdie at five kept Lee at even par only for a bogey at the par-5 sixth to drop her down to one-over at day’s end.

Playing in her first major championship in the US, it was a largely uneventful round of 72 for Kyriacou.

The two-time Ladies European Tour champion began her round with 11 straight pars, exchanging a birdie with a bogey at three and four before closing with five more pars.

KPMG Women’s PGA Championship – Round 1
Congressional Country Club, Bethesda, Maryland
1            In Gee Chun       64
T6          Hannah Green   71
T15        Stephanie Kyriacou         72
T30        Minjee Lee         73
T30        Sarah Kemp       73
T50        Katherine Kirk    74
T72        Su Oh    75
T115      Sarah Jane Smith             78