The American knows full well that matchplay golf can be extremely fickle and he believes his best strategy is to be as aggressive as possible while trying to forget about what happened at Dove Mountain 12 months ago.
"Last year has nothing to do with this year," Mahan, 30, said while preparing for Wednesday's opening round in the Arizona desert. "The road will be just as hard as last year.
"There's no defending here. It's just trying to win this week, trying to beat the guys who are going to play in front of you and that's going to be a tough challenge. The score is kind of irrelevant."
Mahan beat Northern Ireland's Rory McIlroy 2&1 in last year's final to claim his second WGC crown, ending a week of dominant golf that began with his closest match on the opening day.
After scraping past fellow American Zach Johnson in a first-round clash that lasted 19 holes, Mahan took full control of his next five matches while playing what he described as some of the best golf of his life.
"First match last year I didn't play great and I was lucky to get a win versus Zach, but from there I started playing better," he recalled of a week in which he totalled 35 birdies in 96 holes.
"My game from the driver to the putter, every part of it, was strong. It was some of the best golf that I ever played."
Mahan's list of victims last year included US Ryder Cup players Matt Kuchar and Steve Stricker, 2009 US PGA Championship winner Yang Yong-eun of South Korea and McIlroy, who was then the world number two.
The American did not trail in any match that week after the third hole of his encounter with Yang in the second round, a contest he went on to win 5&3, and he is aiming for a similarly aggressive approach this week.
"You've got to be aggressive from the first tee, try to hit a lot of good quality shots and try to put pressure on your opponent," said Mahan, who will face Italy's Matteo Manassero in the opening round on Wednesday.
"You have to play good. That's the only thing that matters. There's no sort of lucky charm or anything like that "This isn't really a place to sit back and let your opponent make a mistake. That's when you're going to lose."
Asked who he rated as the best matchplay golfers assembled at Dove Mountain this week, Mahan replied with a grin: "(Ian) Poulter, I think Tiger (Woods) is a great match play player and probably Luke Donald.
"Luke is just the ultimate match play player because he's a guy that can easily chip in from anywhere, change the kind of momentum of a match. He's a great putter. No matter where he is, he's never going to be really out of a hole.
"Poults just has a will about him that makes him a good player. And then Tiger is just a great player in general, and he just doesn't like to lose. That's always a great motivator."
American world number two Woods is a three-times champion at the event, Poulter clinched the title in 2010 and fellow Englishman Donald followed suit in 2011.