Amateur Mafy Singson blew an early three-under card on a backside foldup but holed out with a birdie to salvage a 72 and tie Harmie Constantino at the helm at the start of the ICTSI Riviera Ladies Challenge on Wednesday in Silang, Cavite.

In a day of shifting fortunes in sweltering heat at the Couples course, Daniella Uy surged ahead in the last flight with one-under card after 15 holes but bogeyed Nos. 16 and 17 then flubbed a birdie putt from pin-length high on the last to drop to joint third with Chanelle Avaricio and Marvi Monsalve at 73.