For the Scottish cyclist it marks an opportunity to say goodbye to a sport that, at different times, has made and broken him. Millar, who will also contest the road race on Sunday, is expected to compete only a handful more times before bringing the curtain down on a 17-year professional career.
Having been dropped by his professional team Garmin-Sharp for the Tour de France due to doubts about his fitness, the 37-year-old said he was feeling in decent form ahead of today's time trial and that his preparation has come together better than he thought it would four weeks ago.
"When I found out I wasn't going to be doing the Tour I thought it was all going to come crumbling down," he acknowledged. "But it's ended up being really good and I've managed to get myself back in the game, as they say. I've been training hard for two-and-a-half weeks and feeling pretty good."
He was bluntly honest when asked about his hopes for today's event, intimating that his strongest suit may be Sunday's road race. "I'm not confident of winning the time trial but I'm confident that I'm going well, so hopefully I won't be an embarrassment," said Millar. "But I'm really looking forward to the road race. I think I'm ready for that so that will be my best chance."
Millar passed up the opportunity to represent Scotland at the 1998 Commonwealth Games in Kuala Lumpur but said that things had "come full circle". Competing in Glasgow has also helped "put everything in perspective" and salve the wounds of missing out on what would have been his final Tour de France.
"I now understand how much more important this is to me than racing for a corporate team," he said. "Pulling on a jersey and racing for Scotland is who I am."
It is Millar's belief that competing in today's time trial would be a "less emotional" experience than in Delhi, but equally he hopes to be buoyed by the cheering spectators lining the road race route on Sunday. "I've got to keep my head on as the time trial is such a cold and calculating event," he said. "In the road race I think it won't be such a bad thing to tap into those emotions because it's going to be a pretty crazy race, especially with the home crowd.
"I'll probably get carried away, as tends to happen. Hopefully it will happen because that will work well for me. It's a bit of a cliche, but this is a once in a lifetime experience. It's my last chance."
Millar, who was suspended from professional cycling between 2004 and 2006 after admitting to taking the banned blood-boosting hormone erythropoietin (EPO), now sits on the athletes' commission of the World Anti-Doping Agency.
Born in Malta, he spent his early years in Lossiemouth, where his father Gordon, a pilot, was stationed. While he has also lived in Hong Kong, France and Spain, Millar's fond memories of Glasgow, where he and sister Fran would visit their grandmother in her tenement flat in Maryhill, endure. That feeling was only strengthened during the darkest days of his cycling career.
"I saw Scotland as a haven during my ban," he said. "It's a haven being among Scots wherever I am in the world. When you do hang out with them I suddenly realise all the quirks I have in my personality are perhaps more to do with my background.
"I felt that the Scots were the most forgiving and understanding of me when all the s*** went down. I'd come to Edinburgh and Glasgow and some people would recognise me and just come up and say: 'You all right, big man?'
"They would treat me very normally. It meant a lot at the time. It's the only place in the world where people call me 'Davie Millar'."