The Vancouver player was on the court for almost six hours Monday as he continued his impressive run at Wimbledon. Hours after coming back from two sets down to beat Viktor Troicki in the fourth round of the men's singles, Pospisil and doubles teammate Jack Sock staged another two-set comeback before ultimately falling to Australia's John Peers and Britain's Jamie Murray.
"It was a long day, for sure," Pospisil offered as an understatement to kick off his press conference after the doubles loss. "Pretty tired right now, but I have a day off tomorrow, so that's good."
He will need all the rest he can get, as his quarter-final opponent on Wednesday is No. 3 seed and 2013 Wimbledon champion Andy Murray. The Scotsman is bound to have a loud cheering section at the All England Club.
"Obviously I played a lot of tennis, but one day recovery is a lot," Pospisil said. "So I can sleep well tonight. Just have a full day of rest tomorrow. Do a lot of recovery ... then come out strong on Wednesday and take it to him."
The unseeded Canadian advanced to the men's quarter-finals after a 4-6, 6-7 (4), 6-4, 6-3, 6-3 win over Troicki, the No. 22 seed from Serbia. The match took two hours 39 minutes, and that wasn't even his longest of the day.
"It was tough. I didn't have the start I wanted to have, and then ... I got unlucky a little bit in the (second set) tiebreaker there," Pospisil said. "I made a couple of good adjustments on my return games. And even being down two sets, it didn't faze me. I feel I'm pretty tough that way. Even if I'm down, I'm always finding ways to come back."
Murray has beaten Pospisil in hard-surface tournaments at Rotterdam and Indian Wells this season, but said he is expecting a tougher challenge from Pospisil on grass.
Murray said he hopes Pospisil's fatigue comes into play.
"After today maybe he's a bit tired. But he will be confident after coming form two sets down and feeling good about his game," said Murray, a 7-6 (7), 6-4, 5-7, 6-4 winner over Croatia's Ivo Karlovic. "He has a game which suits grass and he likes to come to the net."
Pospisil, the world No. 56, had never previously been past the second round in singles play at the All England Club. His previous best singles showing at a Grand Slam event was a third-round appearance at the Australian Open (2014, 2015).
He's hoping to become just the third Canadian to reach the men's singles semifinals at Wimbledon. The others are Robert Powell (1908) and Milos Raonic (2014).
It's almost the reverse story for Pospisil in doubles. The Canadian partnered with Sock to win the Wimbledon men's doubles title last year, but the duo was ousted in the third round 6-3, 7-6 (6), 6-7(5), 3-6, 8-6 by Peers and Jamie Murray in a match that lasted three hours 19 minutes.
Pospisil and Sock appeared to lack energy early in the match, but were energized by a controversial call that went against them in the third set.
With the tiebreaker tied 1-1, a Pospisil volley appeared to go off Peers' racket and out of play. But the umpire ruled that Pospisil hit the ball out of bounds.
Pospisil and Sock argued with the referee before turning their ire toward Peers.
"You want to take the point? Keep your mouth shut," Pospisil said to Peers before adding an expletive.
When a heckler yelled at the duo to get back to playing tennis, the pair had words with the crowd.
"Yeah, it fired us up. But the ball hit the racket of Peers, and it's not that he didn't say anything, but he said he wasn't sure if he hit it," Pospisil said.
"He said he didn't feel it, but it was clearly not the case. So that got us really fired up."
Pospisil, who reached a career-high No. 25 in the singles rankings last year, turned pro in 2007 and is still looking for his first ATP title. He made it to the final at last year's Citi Open in Washington before falling to Raonic.
Earlier Monday, the 11th-seeded duo of Daniel Nestor of Toronto and India's Leander Paes dropped a 6-3, 7-5, 3-6, 2-6, 6-2 third-round decision to eighth-seeded Alexander Peya of Austria and Bruno Soares of Brazil.
Nestor is also playing in the mixed doubles competition with Kristina Mladenovic of France. The eighth-seeded team received a first-round bye and will take on Ken Skupski and Johanna Konta of Britain in the second round.