China's Shanshan Feng added a 70 to her opening 66 to lead the US Women's Open by two strokes but Leona Maguire and Stephanie Meadow missed the cut in New Jersey.
Meadow added a one-over 73 to her opening 77 to miss out by four strokes on six over with world amateur No 1 Maguire three strokes further back after rounds of 75 and 78.
Both Meadow and Maguire will now move on to the LPGA Tour's Marathon Classic at Highland Meadows Golf Club in Ohio next week (Field).
“The course was already long and that made it even longer,” 27-year old Fen said of the rain that delayed play for two hours on Thursday afternoon and fell for much of the day on Friday at Trump National in Bedminster.
“My front nine, I almost had to add 10 yards on some holes. I was hitting a lot of hybrids and 5-irons into the greens. Good thing that I actually hit them pretty well.”
Feng leads on eight-under-par 136 and is seeking to become the second player from the People’s Republic of China to win a USGA championship.
She would join Fumie (Alice) Jo, who won the 2014 U.S. Women’s Amateur Public Links Championship.
She leads three players from the Republic of Korea — Amy Yang, Jeongeun Lee and amateur Hye-Jin Choi, who joined Feng at eight under late in her round before back-to-back bogeys.
Not since Michelle Wie in 2005 has an amateur held a share of second place through 36 holes in the Women’s Open, and Choi’s total of 138 is the best since Grace Park shot 137 for 36 holes in 1999.
Korea's Seon Woo Bae is alone in fifth place on five-under 139, one shot ahead of four players, including 2011 winner So Yeon Ryu and 2015 winner In Gee Chun, both of Korea.
They are joined by Carlota Ciganda, of Spain, and Haru Nomura, of Japan.