Winner of the 2017 season-ending MCB Tour Championship in Mauritius, the Thai made par on the 18th at the fourth attempt, beating Dennis who kept pace with him for three extra holes at Sharjah Golf & Shooting Club.
Fowler was knocked out of the play-off after a bogey on the first extra hole, leaving Dennis and Wiratchant to do battle under floodlights as darkness fell on the Emirate of Sharjah.
“It was really difficult out there today,” said Wiratchant. “The first day was easier because I played in the morning and the greens weren’t as hard. The pin positions were tough today.
“I had to be so patient during the play-off, it was tough playing the 18th four times. I have never played in the dark before, it was tough to adjust and not lose concentration.
“I am so happy to win my second Staysure Tour title. I want to be consistent and have a really good year.”
Wiratchant started the day tied for the lead with Dennis on 11 under par, but the pair found themselves trailing Fowler, who carded a course record of 64 in Friday’s second round, for most of the afternoon on the nine-hole Peter Harradine-designed layout.
The 51 year old moved to 12 under par after a birdie on the fourth hole, but Fowler drew level after a birdie on the second hole and his third eagle of the weekend on the sixth/15th hole.
A bogey on the ninth from Wiratchant, his only dropped shot of the 54-hole tournament, saw him trail Fowler and the Australian increased his advantage with a birdie on the 13th.
Fowler then dropped a shot on the 17th, and Dennis, who was level par through 17 holes, birdied the last to force a three-man play-off.
After Fowler’s elimination, Dennis and Wiratchant both parred the 18th hole three times, before Dennis found trouble with his fourth tee shot, and the subsequent recovery, and Wiratchant tapped in for par and a winner’s cheque of more than €51,000.
The next event on the 2018 Staysure Tour schedule is the KitchenAid Senior PGA Championship at Benton Harbor, Michigan, United States, the week before the Tour returns to Europe for the inaugural Shipco Masters promoted by Simon's Golf Club, Denmark.