Newly married Djokovic, who needed almost three hours to get past Gael Monfils in his opening tie this week, looked under-prepared against Tsonga, the powerful French 13th seed.
The Serb was joined on the sidelines by his doubles partner Stan Wawrinka, with the Australian Open winner losing to Kevin Anderson 7-6 (10/8), 7-5.
Wimbledon champion Djokovic finished with 18 unforced errors and dropped serve four times.
“I didn’t play even close to what I intended before going to the court, just nothing was going — no baseline, no serve, no return,” said Djokovic. “It was just generally a very bad day, very poor performance. I couldn’t do much.”
Two-time Canadian winner Federer was meanwhile forced to the limit by Croatian Marin Cilic, with the Swiss second seed finally claiming a 7-6 (7/5), 6-7 (3/7), 6-4 win on his seventh match point.
Cilic ignited the drama in the 10th game of the second set, holding serve in the 19-minute epic and saving six Federer match points on the way to levelling at a set each.
Federer, who turns 33 on Friday, finally regained control late in the third set as he converted after more than two-and-a-half hours on the court.
“It was a thrilling match and I hope to keep it up tomorrow,” said the relieved winner, who next faces David Ferrer in the quarter-finals. “I was unlucky with some shot selections on some of the match points and he hung in there.
“It was nice to win this one as I’ve had some tight losses this season. In the third set, his level didn’t drop, I just had to keep going and try to create chances.”
- ‘Play with your mind’ -
Djokovic cut a disconsolate figure after his surprisingly heavy loss.
“Obviously I feel disappointment and I’m trying to understand what I did wrong. Confidence is the hardest thing to get but easiest thing to lose. Matches like this can really play with your mind,” he said.
“I didn’t feel exhausted or something like that, but even in the first match (almost three hours against Monfils) I was not feeling very comfortable on the court. I wasn’t hitting the ball clean and made a lot of unforced errors.”
Tsonga saved a break point in the final game of the 63-minute rout, with the heavy hitter pounding over a serve which Djokovic could not handle on match point.
Djokovic came to Canada having won five of the last six Masters events he had contested.
Thursday’s loss was only his fifth of the season against 38 wins.
The victory marked the third time that Tsonga had beaten a world number one after putting out Rafael Nadal at Queen’s three years ago and defeating Federer in Canada in 2009.
“For me today it was great, I played a good match,” said Tsonga. “I was in good condition from the start, I served pretty well. I was pretty aggressive, it’s something positive for me.”
Tsonga next plays Andy Murray, who made the quarter-finals without hitting a ball when scheduled opponent Richard Gasquet withdrew with an abdominal strain.
Spain’s fifth seed Ferrer saved six break points in the second set in his comeback win over Ivan Dodig 1-6, 6-3, 6-3, while Canadian sixth seed Milos Raonic kept home hopes alive by beating France’s Julien Benneteau 6-3, 4-6, 6-4 with 15 aces, taking four match points to go through to his third straight Canadian quarter-final.
Raonic takes on Spaniard Feliciano Lopez, a winner over Czech fourth seed Tomas Berdych 3-6, 6-3, 6-4. Seventh seed Grigor Dimitrov advanced into the last eight as he beat Tommy Robredo 7-5, 5-7, 6-4.
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