Of all the tournaments staged since ATP rankings began in 1973, Montreal marks the first that the world's top eight have fought their way to the quarter-finals of the same event.
Friday's high quality line-up will include players from eight different countries, four past champions and four Grand Slam winners. Among them, only American world number five Andy Roddick has not claimed multiple titles this season.
"It's actually a little bit easier here because the top eight had a bye, but at the same time it's not just the top eight seeds it's the top eight ranked players in the world," Federer told reporters. "It's definitely a special occasion.
"It just shows the top guys now are really consistent and they're showing up at the big events," the Swiss world number one added.
"It's nice it finally happened."
Joining Federer and Roddick are world number two Rafael Nadal of Spain, Briton Andy Murray (3), Serbia's Novak Djokovic (4), Argentina's Juan Martin Del Potro (6), Jo-Wilfried Tsonga of France (7) and Russian Nikolai Davydenko (8).
JOINING THE PARTY
Federer, playing in his first event since clinching a record 15th Grand Slam title at Wimbledon last month, was last to join the party, but his attendance was never seriously threatened by Wawrinka, his partner for doubles gold at the 2008 Beijing Games.
After surrendering the first set, the Swiss number two fluffed a chance to break Federer in the second, and betrayed his frustration by blasting a ball out of the stadium.
Big-hitting Tsonga stands in the way of a semi-final berth for Federer, the Frenchman advancing with a 6-3, 6-3 win over compatriot Giles Simon.
Defending champion Nadal gave his knees a proper work-out in an energetic 6-3, 6-2 win over Germany's Philipp Petzschner, and showed his delight with a buoyant post-game dance around centre court amid wild applause from fans.
"A little better, the movement was a little better," said Nadal, who had been sidelined for two months with tendonitis in both knees prior to Montreal.
"I am happy because I am in the quarter-finals and it is more than I expected when I came here."
Nadal can expect a much sterner test against Del Potro, who is in superb hard-court form after winning the Washington Classic last week.
The Argentine did it tough in his third-round match with Victor Hanescu of Romania, however, coming back from a set down to win 3-6, 6-3, 6-4.
Murray's hardcourt campaign moved into top gear with a 6-1, 6-3 win over resurgent Juan Carlos Ferrero, denying the Spaniard revenge for his quarter-final defeat at Wimbledon.
Playing his first event since falling to Roddick in the Wimbledon semi-finals, Murray knocked the last bit of rust off his game to blast past Ferrero in just 77 minutes.
Murray next meets Davydenko, a 7-6, 7-5 winner over Chile's Fernando Gonzalez.
Unlike Murray, who barely broke sweat under a blazing Canadian sun, 2003 champion Roddick was left drained after his two hour and 36 minute defeat of feisty Spaniard Fernando Verdasco 7-6, 4-6, 7-6.
The win set the American up for quarter-final showdown with 2007 winner Djokovic, who beat Russian Mikhail Youzhny 6-3, 6-4.