(REUTERS) - Ariya and Moriya Jutanugarn of Thailand combined for an 11-under 59 on Thursday (July 15) to take the second-round lead at the Dow Great Lakes Bay Invitational, an LPGA Tour team event at Midland Country Club in Midland, Michigan.

Playing the round under a better-ball format, the sisters made six birdies on the front nine and five more on the back, including No. 18, to score golf's hallowed number.

In the tournament's debut year in 2019, one round of 58 and one 59 were scored during best ball.

Annika Sorenstam is responsible for the LPGA's only stroke-play 59 at a tournament in 2001.

That will not stop the accomplished LPGA veterans from celebrating for now. The Jutanugarns moved to 14-under 126 for a two-stroke lead over the tandem of India's Aditi Ashok and Thailand's Pajaree Anannarukarn (63).

Tied for third at 11 under were South Koreans Hur Mi-jung and Lee6 Jeong-eun (62) and Thai teammates Wichanee Meechai and Pavarisa Yoktuan (63).

The best-ball format led to a number of other low scores. Chinese Taipei duo Hsu Wei-ling and Lee Min posted a 10-under 60 for a 16-shot improvement over their opening-round score.

Four teams carded a 61: South Korea's Kang Hae-ji and Amy Yang (131); compatriots Ji Eun-hee and Kim Hyo-joo (132); Brittany Altomare and Angel Yin; and fellow Americans Jennifer Chang and Kristen Gillman (both pairs on 133).

The field played alternate shot for the first round, and Friday's third round will be the same before better ball returns in the final round.

First-round co-leaders Nelly and Jessica Korda managed only a 69 on Thursday and dropped out of the top 20 as a result.