PATTAYA, Thailand (AFP) ― World No. 1 Park In-bee is under severe threat of losing the top ranking as she makes a delayed start to the season with her LPGA Thailand title defense from Thursday.

The South Korean has held the top spot for 45 weeks, but her formerly healthy lead has been whittled away by Norway’s Suzann Pettersen and could disappear altogether in Pattaya.

Pettersen missed a great opportunity to overhaul Park last week when, needing a strong finish at the Women’s Australian Open, she shot a disappointing 80 in her final round.

Park, 25, skipped the year’s first two events in the Bahamas and Australia, but she will be hoping her luck holds in Pattaya where she was handed last year’s win on a silver platter.

Park was two shots behind Ariya Jutanugarn when she finished her final round, but minutes later the Thai teenager gut-wrenchingly triple-bogeyed the 18th hole to cede the tournament.

It was a stroke of fortune which kicked off an amazing run for Park, who won five more titles including three successive majors in the next few months as she dominated women’s golf.

However, she has not managed a victory since the U.S. Women’s Open in June, and will need to reassert herself quickly if she is to stay at the top of the rankings.