CHONBURI, Thailand (AP) — Yani Tseng’s recent resolve to relax under pressure was tested last month on the final hole in the LPGA Thailand.

The Taiwanese star needed to get up and down for birdie from about 100 yards to avoid a probable playoff after Ai Miyazato hit her approach close.

Meeting the challenge with a shot fitting her No. 1 ranking, Tseng controlled the spin perfectly to set up a tap-in putt for a one-stroke victory over Miyazato.

"It was an incredible shot. I think it’s the shot of the week," Tseng said. "Especially, I saw that Ai hit it so close and I knew she was going to make that putt. So, I tell myself, ‘I need to get this close."’

The 23-year-old Taiwanese star successfully defended her title for her 13th Ladies Professional Golf Association Tour victory, matching Miyazato with birdies on the final two holes to hold off her Japanese friend by a stroke.

"It was tough," Tseng said about her approach on the par-5 18th hole. "I had 104 to the pin and a little uphill. I know my ball is going to spin a lot, so I just tried to keep it low and not spin too much. ... I was very proud of myself for hitting that shot into 18 and making birdie to win."

Tseng closed with a 6-under 66 to finish at a 19-under 269 on the Pattaya Old Course at Siam Country Club.

She has been working to handle the pressure that has come with the No. 1 ranking and her 12 worldwide victories last season.

"After last year, I have world No. 1 and I had 12 wins and that pressure keep going on and on," Tseng said. "I kind of drive my team crazy. They were thinking I feel so much pressure. So, sometimes I wasn’t happy and I wasn’t quite nice to them. They keep telling me, ‘Think you have some pressure, you need to relax yourself.’ We kind of have a team meeting to keep me relaxed and not feeling like I had pressure. So I think my team did a great job and helped a lot through this week. It was just great. I feel really good about that."

Tseng opened with a 73, then shot consecutive 65s to enter the final round a shot behind Miyazato.

"I had some luck out there," Tseng said, pointing to the lucky Thai statue where she made a wish. "I shot 1 over the first round, but I came back very soon and played 20 under the next three days. I felt like I could improve a lot and I feel like something gave me luck."

She also visited the statue last year.

Last year, Tseng won the event for the first of her seven 2011 LPGA Tour victories, including major victories in the LPGA Championship and Women’s British Open. The five-time major champion has 33 career worldwide professional victories.

Miyazato finished with a 67.

"Of course, Yani is No. 1, so I knew it wouldn’t be easy today," Miyazato said. "I kind of expected her to play that way."

South Korea’s Jiyai Shin, tied for the lead with Tseng after a birdie of her own on the par-4 17th hole, had a 67 to finish two strokes back.

Tseng eagled the par-5 opening hole and Miyazato had a birdie, leaving them tied at 15 under. Tseng took the lead with a birdie on the par-4 third, and added birdies on the par-4 sixth and par-5 seventh. At the turn, she had a three-stroke lead over Shin and a four-shot advantage over Miyazato.

"I played really well on the front nine, but it was tough on the back nine, especially when you see Jiyai and Ai keep making birdies," Tseng said. "It got tight down the stretch. It was tough. I feel like I had lots of emotions today."

Shin, playing a group ahead of Tseng and Miyazato, birdied the par-4 10th to pull within two and gained another stroke when Tseng bogeyed the hole. Tseng pushed her lead to two with a birdie on the par-3 12th, but bogeyed the par-4 13th.

Miyazato birdied the 10th and pulled within one of Tseng with a birdie on the par-4 15th, then matched Tseng with a par on 16 and birdies on 17 and 18.

"Overall, I played really well and I’m very happy that I could finish strong today," Miyazato said. "I really enjoyed playing with Yani, but next time I want to win."

South Korea’s Amy Yang shot a 69 to finish fourth at 14 under.

Sixteen-year-old Thai amateur Ariya Jutanugarn followed her third-round 65 with a 74 to tie for 12th to 7 under. She played the final five holes in 4 over, making a double-bogey 7 on No. 18. Last year, Jutanugarn won the U.S. Junior Girls’ Championship and was the Rolex Junior Player of the Year.