The Canadian had a two-shot lead over South Korean Ryu So-yeon going into the last day of competition, with at least four shots to the rest of the field.

However, she struggled again on the first hole, scoring a bogey before four pars in a row.

It only got worse on the sixth with a double bogey.

Fortunately, Ryu had just scored a double bogey of her own on the previous hole and was falling down the standings.

It was Schubert that started to emerge only a few shots behind Henderson and soon matched the leader near the end of the round. 

With it looking as if the Canadian had blown her chance to win the title outright and a playoff looming, Henderson putted for a birdie on the 18th to seal the victory as Schubert putted for par.

Henderson ended the day on par for an overall score of 17-under, one shot in front of Schubert.

Japan's Mao Saigo ended up with the best round of the day on seven-under to finish tied for third on 15-under overall.

Despite putting for two bogeys, the Japanese golfer claimed nine birdies.

Joining her on that score were the late-surging Australian Lydia Ko, Charley Hull of England, South Korea's Kim Hyo-joo and Carlota Ciganda from Spain.

Linn Grant of Sweden scored seven-under today too to finish tied for eighth on 13-under, matched by England's Georgia Hall, who scored six-under for the day.

World number one Ko Jin-young struggled to capitalise on Henderson's mistakes, finishing with Grant and Hall, but with a day score of two-under par along with American Olympic champion Nelly Korda and her compatriots Kim Sei-young and Ryu So-yeon.

Ryu scored two-over for the day, plagued by two double bogeys and two bogeys.