Daniel Nestor has one more shot at winning another Olympic medal—even if he didn’t seem too pleased about it on Thursday.

Nestor and partner Vasek Pospisil lost to the Spanish duo of Rafael Nadal and Marc Lopez in a tightly-fought contest 7-6 (1), 7-6 (4) in the men’s doubles tennis semifinals, putting the Canadians into Friday’s bronze-medal match.

Rio 2016: Vasek Pospisil and Daniel Nestor, tennis

Canada’s Vasek Pospisil and Daniel Nestor take on Spain’s Raphael Nadal and Marc Lopez in Rio 2016 men’s doubles on August 11, 2016. COC Photo/David Jackson

But 43-year-old Nestor, competing in his sixth (and most likely final) Olympic Games, expressed uncharacteristic frustration, both during and after the match, about decisions from the chair umpire.

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Nestor and Pospisil were unable to challenge any decisions during the match, since it was played on Court 3 at the Olympic Tennis Centre, which is not equipped with the HawkEye replay system that fans and players have grown accustomed to.

Team Canada's Daniel Nestor and Vasek Pospisil compete against Portugal in the men's second round of doubles tennis, Rio de Janeiro, Brazil, Monday August 8, 2016. COC Photo/David Jackson

Team Canada’s Daniel Nestor and Vasek Pospisil compete against Portugal in the men’s second round of doubles tennis, Rio de Janeiro, Brazil, Monday August 8, 2016. COC Photo/David Jackson

Nestor—one of the most decorated doubles tennis players of all time—had his sights set on a second Olympic gold for his country, to go along with the one he won with partner Sébastien Lareau at Sydney 2000. As it stands, he and Pospisil, a 26-year-old competing in his second Olympics, will go for bronze against the American team of Jack Sock and Steve Johnson.

Interestingly, Pospisil and Sock have competed as doubles partners on the ATP World Tour in recent years, even winning the 2014 Wimbledon title in men’s doubles together. Only one of them, however, will be leaving Brazil with an Olympic medal around their neck.