The pair, playing in the last group, had finished tied on a 12 under par total of 276 after closing rounds of 68, three ahead of the Swede Robert Karlsson, Germany's Alex Cejka and Spain's Santiago Luna.
And it was the former Walker Cup player Phillips who held his nerve better when it mattered most to earn his first title in only his third full year on tour.
"It feels great and I feel relieved, actually," said Phillips, who moved up to 14th on the Order of Merit and 18th in the Ryder Cup table.
"I've always felt I had the temperament to win and it's been frustrating not to win. But I always believed in myself and felt I was good enough to win."
It was not until 1995 that Phillips made it on to the European Tour and he finished third behind Ernie Els in the South African PGA in his first season.
A tournament win proved elusive until this week but now he has broken his duck, he promised nothing would change. "I'll be back playing next week; it'll be business as usual," he said.
Scores, Digest, page 9