(Reuters) - World number two Brooke Henderson suffered a double bogey on the back nine but the defending champion still finished two strokes ahead of the chasing pack after the third round of the Portland Classic on Saturday.


The Canadian, who won her first LPGA title by eight shots at the Columbia Edgewater Country Club last year, carded a two-under-par 70 for a 13-under 203 total and a two-shot lead over Mariajo Uribe (71).


Henderson, 18, began the third round tied at the top with Suzann Pettersen but the Norwegian carded a sloppy 74 to fall four shots off the pace and into a tie for third with Austin Ernst (69).


Henderson lead by three after carding three birdies on her opening 10 holes but stumbled at par three 13th where her tee shot found water.


“I just mishit it,” said Henderson, who got one of those strokes back with a birdie on 16. “Unfortunately, it hit the bank and bounced back in."


Henderson, who beat world number one Lydia Ko in a playoff at the KPMG Women’s PGA Championship last month, is trying to become the first player to win back-to-back titles in Portland since Annika Sorenstam in 2002 and 2003.

Uribe, seeking her first LPGA win, is at 11-under after a 71. The 26-year-old Colombian, who began the round a stroke behind the leaders, followed Henderson's lead on the back nine with a double bogey at 13 and birdie on 16.

(Reporting by Tim Wharnsby; Editing by Peter Rutherford)