Australian Lleyton Hewitt won his first title since 2010 with a three-set victory over top seed Roger Federer in the Brisbane International final.
Hewitt, 32, beat his fellow former world number one 6-1 4-6 6-3 to win the Australian Open warm-up tournament.
Swiss Federer, also 32, was broken three times in the first set but the 17-time Grand Slam winner fought back to level against the world number 60.
Hewitt saved seven break points on the way to winning the decisive third set.
Federer, who has not won a Grand Slam tournament since Wimbledon in 2012, added six-time Grand Slam winner Stefan Edberg to his coaching team in December.
The Australian Open begins on Monday, 13 January.
And Hewitt, finalist in Melbourne in 2005, said: "If I play like I did this week I have a chance of doing damage to some serious players.
"It gives me a lot more confidence going out there believing in how well I'm hitting the ball at the moment and that I can match up with the best guys."
Hewitt will move back into the top 50 in the world rankings as a result of his victory over Federer, who had not lost a game on serve before the final.
Federer said: "I have a clear idea what I need to work on and I have a clear idea where my mind and body is at."