It was his first European Tour victory since the Jersey Open nearly two years ago and moved him up from 31st to 21st in the Ryder Cup table.
Torrance, who has played in the last six Cup matches, said: 'This is an important win for me. I wasn't really in contention for the team, but now I am.'
He began the day three shots clear of the field, but took three putts on the first hole and was caught at the third by the Italian, Costantino Rocca, who went out of bounds at the fourth and fifth holes, dropping three shots. At the turn, Torrance was six clear.
Miller then took over as the main challenger, making three birdies to close the gap. Torrance struggled on the back nine, but holed his second putt on the final green from 12 inches to win. 'A win is a win and one shot is enough,' he said.Reuse content