Lleyton Hewitt of Australia celebrates his win against Kei Nishikori of Japan during their men's singles semi final match at the Brisbane International tennis tournament in Brisbane, January 4, 2014. [Photo/Agencies]

"You want to play against the best players, and obviously Roger and I have a good history and a lot of tough matches in the past in slams and Davis Cups and everything," Hewitt said. "We're the same age. We grew up together. He's a great guy. I have the upmost respect for him, not only as a player but for what he does off the court as well."

Hewitt handled the heat better than his Japanese opponent as the temperatures topped 104 F (40 C), and his grinding style paid dividends as the match extended to two and half hours.

"I love a battle," said Hewitt, who won the U.S. Open in 2001 and Wimbledon in 2002 and spent 80 weeks at No. 1 before Federer assumed the top ranking and held onto it for four and half years. "Mentally this is a major win to have come back and gone the distance."

Federer said he struggled against Hewitt earlier in his career before getting on top in the rivalry. Now both married with kids, they're occasional practice partners and get on well.

Both players have reflected on a Davis Cup semifinal between Australia and Switzerland at Rod Laver Arena in 2003 as the turning point in their rivalry, and in Federer's career. Hewitt rallied from two sets and a break down to win that match, but it still changed Federer's mindset for the better.

"I was ... serving for the match, ended up losing 6-1 in the fifth," Federer recalled Saturday. "It really proved to me that I could play great tennis not just for a set, two sets, but three sets or maybe even longer against the toughest guys out there.

"And for me to be able to not just do it tennis-wise but physically and mentally gave me the big belief that I could hang with the best _ then I went on a run like I did."