The 26-year-old Olympic silver medallist was targeting a world record and Commonwealth gold in his home pool of Tollcross, only to finish second to Scotland team-mate Ross Murdoch in the 200 metres breaststroke.
For Murdoch it was a coming-of-age performance, “life-changing” according to Jamieson, who was left distraught after falling short of his own expectations.
“The event itself was a real success,” Jamieson, an ambassador for the British Gas SwimBritain events, said. “It was great for the city, it was great for Scotland. I didn’t swim the way that I’d wanted to.”
Did Jamieson, already the poster-boy of the Games, heap too much pressure on himself by outlining his targets in advance?
“I was honest,” he said. “I only spoke about what my targets were. I didn’t come out and say, ‘This is what I’m going to do’. I just said, ‘This is what I’m hoping for’. I’d hope that is noted, because I’m not the kind of athlete that comes out and says, ‘I’m going to win this’.
“The time I had in my head that I was going for was realistic, based on my previous personal best. I just wanted to improve and I wasn’t able to do it.”
The frustration was obvious in the immediate aftermath, but Jamieson is magnanimous in defeat.
“He [Murdoch] deserved to win,” Jamieson added. “He swam really well, posted a world-class time.”
Rather than getting back in the pool and racing at the European Championships in Berlin, an event which took place just a few weeks after Glasgow 2014, Jamieson went on holiday and did not take his trunks.
“I’ve been using my time away from the pool to take my head away from the sport a little bit and just try to prepare for the next season,” said Jamieson, whose 2015 target is the World Championships in Russia.
Rio remains the long-term target.
“It’s natural to be disappointed after a result like I had,” he said. “In sport it’s just about trying again. There’s no other option. That’s what I’m going to try to do.
“It would be foolish not to [aim for Rio]. Despite how disappointed I was, I’m still ranked number three in the world.
“It would be ridiculous to consider walking away from the sport in that position.”
Jamieson’s return to the water began with the British Gas SwimBritain events, which have put competition in perspective as he was among children thrilled to be in his company.
“There are so many young kids here so excited about swimming and it’s nice to be a part of that,” he added.
Jamieson is based in Bath and has no vote in today’s Scottish independence referendum.
“Until the last week I hadn’t made much of an effort because of that,” he said. “I’ve been watching a few debates here and there and trying to get sense of both sides of the argument.”
He is uncertain what his vote would be, but is proud to compete under both the Saltire and Union Flag.
“We have only ever been in that position,” he said.
“That’s all we’ve ever known as an athlete, to represent your home nation at the Commonwealth Games and represent the union at an Olympic Games and the World Championships. It’s a privilege to represent both.”
• Michael Jamieson was speaking at British Gas SwimBritain in Bristol and will be at the Glasgow event on 28 September. Go to www.swimbritain.co.uk to sign up.