Jennifer Johnson fired a 7-under 65 on Sunday and earned a 1-stroke win at the Mobile Bay LPGA Classic.
Johnson, who won for the first time on the LPGA Tour, finished 21-under-par 267. Her total of 267 bettered the tournament's scoring record by four shots. Stacy Lewis set the old record of 271 last year.
"I'm a little shocked. I didn't even realize I shot 65. The whole back nine ... I don't know what was happening. (After) the birdie putt on 17, that's when I started to think a little bit more about winning the tournament."
Pornanong Phatlum fired a 9-under 63 to grab a share of second place. She was joined at minus-20 by Jessica Korda, who closed with a 4-under 68.
Third-round leader Chella Choi carded a 2-under 70 in the final round. She shared fourth place at 19-under 269 with Karrie Webb (68), Jiyai Shin (63), Anna Nordqvist (69) and Ariya Jutanugarn (65).
Lewis, last year's winner, posted a 67 in the final round to end alone in ninth at minus-18 on the Crossings Course, which is part of the Robert Trent Jones Golf Trail at Magnolia Grove.
On a day when six different players had at least a share of the lead, Johnson broke through the pack with a late surge.
She was 3-under par for the front nine with a bogey and four birdies, then parred three in a row from the 10th. Johnson stuffed her third within inches of the hole at the par-5 13th and kicked that in for birdie and a share of the lead.
Johnson came right back with a birdie on the par-3 14th to move one clear of the field. As she parred the 15th, Johnson was joined atop the leaderboard by Korda, Phatlum, Choi and Shin.
Phatlum birdied the 18th for her fourth birdie in the last five holes. That briefly gave her a 1-shot lead, but Johnson joined her there with a 2-putt birdie at the 16th.
Johnson, who earned the winning point for the 2010 U.S. Curtis Cup team, made it two in a row as she also birdied the par-3 17th from about 15 feet out. She parred the last, then waited for the final two groups to finish to see if anyone would catch her.
"It was pretty intense for me. I was telling my caddie, man, I haven't seen that much tension on a golf course in a while," Johnson said. "And he's telling me what, what's intense? So he was trying to keep me loose, crack some jokes."
Korda and Webb both birdied the last, but needed more to gain a share of the lead. That left it up to the final group, Choi and Nordqvist. If either were going to force a playoff, they would have to sink their second shots at the par-4 closing hole.
Both players hit solid approach shots, but neither came close to going in. And those misses gave Johnson her first LPGA Tour title.
Early on, Korda birdied three of four holes from the third to grab the lead. When she bogeyed the seventh, she fell into a tie with Choi.
Choi closed the front nine with birdies at eight and nine to make the turn with a 2-shot lead at 20-under. However, she tripped to bogeys at 11 and 12 to fall into a tie for the lead with Johnson.
Choi moved back to 19-under with a birdie at 13. Korda, who dropped another shot at 12, birdied 13 and 15 to join Choi, Phatlum, Johnson and Shin in the lead. Johnson then pulled away from everyone with birdies at 16 and 17.
NOTES: Johnson earned $180,000 for her first tour win ... Her best previous tour finish was a share of eighth at the 2011 Navistar LPGA Classic, which was on another course of the Robert Trent Jones Trail in Alabama ... The LPGA Tour heads to the Bahamas next week for a new event, the Pure Silk-Bahamas LPGA Classic.