Calder, a gentle giant at six foot four and 210 pounds, worried about letting people down.
Calder and Scott Frandsen, silver medallists four years ago in Beijing, placed sixth in a race dominated by a swashbuckling New Zealand duo yet to taste defeat.
The Canadians rowed their race Friday. It just was nowhere near good enough.
"It's going to be hard to go back and face all the people who were behind this silver to gold campaign that we created," said the 34-year-old Calder, his voice breaking.
"And there's been so much support, especially coming from Victoria, but from all across Canada. I'm proud of what we've done here, but I really wanted to walk away with a medal. I really wanted to challenge those Kiwis.
"Nobody back there's going to judge me for it. Nobody back there's going to think anything less of me. But in my heart, I wanted to win for me and I wanted to win for everybody's who's been behind me all this time."
Hamish Bond and Eric Murray, who set a world best in their opening heat here, won gold for New Zealand in six minutes 16.65 seconds. France was second in 6:21.11 and Britain third in 6:21.77.
"We had the speed. No one else sustained it," Murray said simply.
For Rowing Canada, it was another medal missed.
"Not what we expected," said high performance director Peter Cookson. "These guys are high-calibre guys. They clearly didn't meet their expectations."
There is one day left in the regatta but Canada is done in races that matter.
After collecting a gold, a silver and two bronze in Beijing, the Canadian team will leave Eton Dorney with a pair of silvers from the men's and women's eights.
More was expected.
Cookson looked long and hard for positives. He ended up counting bodies rather than medals.
"I think what I am proud of is that we're finished our A finals now and we had 16 athletes, excluding the coxes, on the podium. Or 18 if you include the coxies. That's a lot for any sport. That's the first time since 1992 that we've had two eights on the podium. I think that's a real major accomplishment for the team.
"And in Beijing, in 2008, we had also 16 athletes on the podium. We've matched it again."
Bottom line is the two medals represent the bottom end of any projection for a rowing program that has received $7,444,000 from Own The Podium since 2008. Cookson himself said he thought he would get five to six finals out of his seven boats.
He got three.
"I don't know all the reasons yet," he said.
Asked if his pride in the team was shared with disappointment in the results, he replied: "That's fair to say."
Everything will be up for review, he said.
The French came out fast Friday but New Zealand ran them down around 750 metres. The Kiwis led by 5.2 seconds after 1,500 metres and won in a walk, preserving their career unbeaten record.
New Zealand had the fastest split times over the last 1,500 metres. Canada, meanwhile, was fifth at every split before fading to sixth in 6:30.49.
"I think we did race our game," said the 32-year-old Frandsen. "I think we did pretty well. It just wasn't what we needed."
Strong winds prompted a re-draw of the lane allocations for the finals, which alternated between sunshine and grey skies and sporadic rain at Eton Dorney.
The top qualifiers from the semifinals were placed in lanes 5 and 6, where they would be better protected from the wind. That meant Calder and Frandsen were switched from lane 6 to 2.
"It was right and just to reset it," said Calder, a four-time Olympian who also retired after Athens. "Again it's too bad that we didn't capitalize on the semifinal so that we weren't burned. I mean it's our fault to place third in the semifinal, and the consequences in an outdoor sport are such that if the fairness committee makes the call, we get hit with a bad lane."
The Kiwis, meanwhile, cemented their status as the rock stars of rowing.
Bond and Murray switched to the pair after their world champion four failed to make the final at the Beijing Olympics and finished seventh.
Since joining forces in 2009, the three-time world champions have never been beaten. Their website (www.kiwipair.co.nz) lists 41 races, from heats to final, exluding these Olympics. They have won them all, including 14 World Cup and world championship finals.
They have been so dominant that the three-time world championship silver medallists Peter Reed and Andrew Triggs-Hodge of Britain, after losing 14 straight to the New Zealanders, switched to the four.
The New Zealanders' recent world best of 6:08.50 took almost six seconds off the previous mark of 6:14.27, set in 2002 by James Cracknell and Matthew Pinsent.
Winning never gets boring, Murray said before the final.
"Hell no," said the six-foot-four 214-pounder, whose angled sideburns and Fu Manchu moustache make him look like he should be wielding a guitar for Motorhead rather than an oar.
"We find it's better to be in the position that we are because we know that we can win whereas all the other crews don't think they can beat us. They don't know they can beat us because they haven't beaten us in the past whereas we beaten every crew that we've come up against. So we can be confident in our abilities."
Calder, from Victoria, and Frandsen, from Kelowna, B.C., retired after the 2008 Games, but returned to the sport after realizing the competitive fire still burned. They put their lives and careers on hold to represent their country again, working under coach Terry Paul.
Asked what's next, Calder pointed down the path to his right.
"They're right over there. My wife and kids are waiting and I'm going to retreat to them," he said. "I'm going to take a little break for a couple of weeks and just decompress, get it all out of my system, figure out some things."
He is not finished with sport, however. He says he wants to help Own The Podium and the Canadian Olympic Committee "continue this pursuit of high-performance excellence."
He says he just has to figure out what he can do to help.
"There are big things in the future," he promised.
Asked whether it was his last Olympic race, Frandsen said it was "way too early to say."
"It's definitely frustrating. The process has been incredibly rewarding. It's been a lot of fun ... It's tough to end it like that," he said, his voice cracking.
While Calder and Frandsen climbed the podium in Beijing, they have both suffered Olympic disappointment in the past.
Frandsen was a member of the Canadian eight that went into the 2004 Games in Athens as the favourite, only to finish fifth.
Calder's Athens experience was equally bleak. He and pairs partner Chris Jarvis were disqualified in the semifinals for clashing oars with another boat after straying into the adjacent lane.
Calder's Olympic career started in 2000, when he finished seventh in the eight.
"I'm really proud to have been able to say that my first Olympic Games was in 2000 and my last Olympic Games was in 2012," he said. "Even though I've walked away with one medal from Beijing, I feel like it's been a lifetime of pleasure.
"Who gets to play for their work, right? Who gets to wake up every morning and hit the lake and work out for their life? I've been so lucky."
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