* Horschel sinks 26-foot birdie putt to earn win
* American closes with a nine-birdie 64
* D.A. Points finishes second after 65
American Billy Horschel charged ahead with six consecutive birdies, then held his nerve down the stretch to win his maiden PGA Tour title by one shot at the Zurich Classic of New Orleans in Avondale, Louisiana on Sunday.
Two strokes off the pace going into a weather-disrupted final round, Horschel took advantage of rain-softened conditions and preferred lies at the TPC Louisiana as he sealed his long-awaited breakthrough victory with an eight-under-par 64.
The slim 26-year-old, who had recorded top-10s in his three previous starts on the U.S. circuit, stunningly drained a 26-foot birdie putt at the par-five last to post a 20-under total of 268.
Horschel repeatedly pumped his right fist in delight after his ball disappeared into the cup for his ninth birdie of the day, then removed his cap to acknowledge loud cheers from the gallery packed around the 18th green.
"Oh man, it's something I have worked so hard for and there are so many people I need to thank. And they all know who they are," an emotional Horschel told Golf Channel after coping with two weather delays during the final round.
"And for that putt to go in ... I hadn't made a long one all week and I said, 'I am due for a long one, I am due for a long one. Just commit to it.'
"It came off the putter so good and I am so happy it went in. This is unbelievable right now."
Fellow American D.A. Points, playing with Horschel, had been tied for the lead with three holes remaining but settled for second place after closing with a seven-birdie 65.
Overnight leader and 2009 U.S. Open champion Lucas Glover, bidding for his fourth PGA Tour victory, fell back with an early bogey on the way to a 71 and a tie for fourth at 15 under.
Glover began the day two strokes in front and he parred the first five holes before play was suspended for about three hours as the first wave of thunderstorms rolled into the area.
At that point, his lead had shrunk to just.
Soon after play resumed, Points and Horschel briefly moved into a three-way tie at the top as they each birdied the par-five seventh before Jimmy Walker sank a 26-foot eagle putt at the same hole to edge a stroke in front.
Glover slid back with a bogey at the seventh after overshooting the green and hitting a poor chip coming back.
Former Walker Cup amateur Horschel also birdied the eighth and ninth to move one ahead at 16 under before being joined by Walker, who rolled in a 10-footer to birdie the par-four eighth.
While Walker stumbled with a double-bogey at the par-three ninth, where his bump-and-run from below the green failed to crest the slope and rolled back to his feet, red-hot Horschel kept charging forward.
He sank a 14-footer to birdie the 10th and a six-footer at the par-five 11th to get to 18 under, two ahead of Points.
Both players picked up a shot at the par-four 12th, Horschel sinking a 15-footer there to tie the PGA Tour record this season of six consecutive birdies.
Horschel, speeding up in his play, bogeyed the 15th after finding the right rough off the tee and missing the green with his approach.
That dropped him into a tie with Points, who had recorded his sixth birdie of the day at the 13th.
Horschel rebounded with a birdie at the par-four 16th after hitting an exquisite approach to four feet to regain a one-stroke cushion.
Play was again suspended, for just under an hour, due to the threat of lightning shortly after Horschel drove into the left rough off the 18th tee.
On resumption, he wisely laid up in two, then struck a wedge approach to 26 feet short of the hole before sinking the birdie putt to clinch an emotional victory.
British world number four Justin Rose, the highest-ranked player in the field, closed with a 69 to tie for 15th at 12 under, level with 2012 Masters champion Bubba Watson (66) and four-times major winner Ernie Els (68).
China's 14-year-old Guan Tianlang, after making his second consecutive cut on the PGA Tour, signed off with a two-over 74 to finish at four-over 292, stone last in the 71-strong field.