KUALA LUMPUR, Malaysia (AP) — Amy Yang took the Sime Darby  Malaysia lead, and Michelle Wie had her best score in more than a year. Lydia Ko had to fight to get back to even par in her first tournament since firing her caddie.

Yang shot an 8-under 63 on Thursday in hot and humid conditions for a two-stroke lead over American Marina Alex. The 27-year-old South Korean player birdied all four par-3 holes at TPC Kuala Lumpur.

Wie opened with a 66, breaking 70 for only the fourth time in 68 rounds this year. Winless in 57 tournaments since the 2014 U.S. Women's Open, she's coming off a season-best 10th-place tie last week in China in the Blue Bay LPGA.

The top-ranked Ko birdied the par-5 18th for a 71. She had a double bogey on the par-4 second.

The 19-year-old New Zealander fired Jason Hamilton, the Australian who caddied for her since late 2014, and is using Malaysia's Sargunan Suntharaj this week. Hamilton shifted to Ha Na Jang and helped the South Korean player open with a 69.

China's Shanshan Feng, the 2014 winner, was at 66 along with Wie, Norway's Suzann Pettersen, American Mo Martin, Spain's Azahara Munoz and South Korea's Jenny Shin.