Lleyton Hewitt won the battle of the former world number ones at the Montreal Masters on Monday by beating Spaniard Juan Carlos Ferrero 7-6, 6-4 to reach the second round.
The Australian, ranked four places below Ferrero at number 21, prevailed in one hour 47 minutes. He will play either American ninth seed James Blake or Juergen Melzer of Austria.
In his first outing since Wimbledon, where he reached the fourth round, Hewitt's greater consistency helped him get past Ferrero, who has shown signs lately of regaining his best form.
After trading an early break of serve, the rest of the first set went with service before Hewitt surged ahead 6-3 in the tiebreak then clinched the set 7-5.
The Australian broke in the first game of the second set and, despite a couple of nervous moments, held the advantage to reach the second round.
"I probably took, maybe, not even a week off after Wimbledon and started hitting balls again, getting into it, in the gym every day," Hewitt told reporters.
"I was just trying to prepare as well as possible for the next few weeks. I enjoy this part of the year. I've always played well on US hard courts and at the US Open."
After winning the title in Las Vegas in March, Hewitt was hampered by niggling injuries for the next two months, but bounced back with a semi-final appearance in Hamburg and solid fourth-round
"Indian Wells and Miami (in March) were frustrating because I was playing well going into those events," he said. "Winning Vegas, I felt like I was starting to turn it around again.
"After Miami, I spent a lot of time in the gym, worked extremely hard to try to get my body right. It held up really well through Rome through to Wimbledon and it feels pretty good right now."
Hewitt is playing doubles in Montreal with world number two Rafael Nadal, something he said he likes to do after a layoff.
"I'm looking forward to it," he said. "I like Rafa a lot. I think he's great for the game. He's got a great attitude. I don't know why the hell he would be wanting to play doubles here after all the matches he's played though. That just says how much he enjoys competing."
Earlier, Tomas Berdych was the first seeded casualty, the Czech 10th seed losing 6-4, 7-5 to 20-year-old Dutchman Robin Haase.
Haase, whose ranking has soared from 669 at the start of last year to its current 103, will now play either former world number one Carlos Moya of Spain or Cypriot Marcos Baghdatis.
David Nalbandian cruised past Alajandro Falla of Colombia 6-4 6-3, while there were also wins for seventh seed David Ferrer of Spain, American Michael Russell and Dominik Hrbaty of Slovakia.