
Baghdatis spent 70 minutes in winning a match that pitted the last two finalists at the Australian Open against one another.
The popular Cypriot raced away to a double-break in the first set in 40-degree temperatures and wrapped up the opener in well under half an hour.
Chile's Gonzalez tried to cut down on the error count, which surpassed 60, but was unable to turn the tide despite saving four match points.
Baghdatis was thanking his luck after being called up as a late substitute for the elite eight-man, round-robin event after Roger Federer, Tommy Haas and David Nalbandian pulled out because of illness or injury.
"I'm very glad I was able to play," the number 16 said of the tournament that serves as a tune-up for the Australian Open, which begins Monday. "I'm happy with how I'm playing. I guess I'm ready for the Open.
"It was good to play in windy, tough conditions. I've had a good week here. I'm playing better and better."
Baghdatis heads into Saturday's final standing 1-2 against Roddick, his win coming against the American at the Open two years ago.
Roddick booked his place Thursday in a third-straight title match at the Kooyong club with a win against Marat Safin.
"I came here to win the tournament," Roddick said. "I won't think about the Aussie Open. I'll do that after the match. I think I have the game to beat anyone."