"I was strolling around the O2 trying to trip people up," says the Scottish doubles player with a smile. An explanation may be necessary. Fleming and his partner Ross Hutchins were alternates for the doubles in the Barclays ATP Tour World Finals and were on hand to step in if there were any late withdrawals.
"Basically we were on site until 6pm when the evening session of doubles began so as to step in if anyone was injured," says the 28-year-old. "There was a frustration at being so close, seeing the flashing prize and not being able to touch it."
The pair could be consoled by the £17,000 they were paid for their watching brief after they finished ninth in the rankings, one place outside qualification. Marcel Granollers-Puyol and Marc Lopez of Spain, the No.6 seeds, won the £200,000 prize on their first visit to the tournament.
"The experience of being at the O2 was excellent, but it has only increased our desire to play in the finals," says Fleming. "It just makes you want to be there, to be out there in that atmosphere"
The drive to succeed, of course, is never a problem for the Scot. This is a doubles act with both motivation and ambition. The year has been so busy that Fleming is only now heading off on honeymoon with his wife, Gemma, just short of 12 months after they were married. "She has been very patient," he admits.
Injuries to both players stalled a promising run and and left the pair just short of the finals. "It was not just the period out, but when we got back together it took us some time to get our act together. We were just rusty, I suppose," says Fleming.
It was still a season marked by progress. The pair finished in the top 10 for the first time and won ATP titles in Delray Beach in March and Eastbourne in June. They were also finalists in Newport and Kuala Lumpur.
Full-time partners since 2011, they won £347,308 in prize money last season and Fleming, a business graduate from Stirling University, is grateful for every opportunity to play in professional tournaments. "I took a break out to live in the real world and it has just made be so thankful to be making a living playing the sport I love," says the Scot who left school to study economics and finance, graduating with a first-class honours degree in 2007 before securing a graduate scheme position as an energy trader where he worked for a year before returning to the tour.
A small child for his age, Fleming has grown to be 6ft 3in but has never lost the competitive spirit that marked him out as a promising youngster.
"We have always been clear about our ambitions," he says of his partnership with Hutchins. "We want to win grand slams, we want to be the best on tour."
He has been energised by the success that now surrounds him in British tennis. "It is great practising at the NTC [National Training Centre] with Laura Robson and Heather Watson about," he says of the two British players who have made giant strides this year. "You can feed off that success and say 'if they can do it, why can't we?'"
His schedule next year will include a Davis Cup tie against Russia and Fleming agrees with Leon Smith, head of player development at the Lawn Tennis Association, that Team GB are one singles player away from being a potential winner of the competition.
"As a doubles team, we are proud of progress and where we stand but are determined to become better and, with Andy in the side, you can just about guarantee two points from the singles. Another top-class singles player would make us a difficult team to beat."
Andy, of course, is Mr Murray, the US Open title winner who was brought up on the courts with Fleming. "It was amazing watching him win at Flushing Meadows," says Fleming. "You grow up with people like Andy, Jamie [Murray] and Jamie Baker and then find we are all on tour, all trying to make a living out of this sport."
The doubles player watched Murray win at his home in Scotland. "This is the sort of thing that sends chills down your spine," he says. "You are watching one of the majors and your friend is winning it. You have some idea of what he has put in to this and the hair on the back of your neck stand up. It was very emotional.
"Andy said it was surreal coming back to Dunblane and getting that welcome from the place where he grew up."
The itinerary for Fleming now includes a trip to South Africa for his honeymoon, before pre-season training in La Manga and then off to the southern hemisphere to begin the quest for a 2013 major at the Australian Open.
It looks like being another year spent in fast forward, but the aim is to end it with a walk-on part at next year's finals at the O2.
n Life and pensions company AEGON, lead partner of British Tennis, provides support to Team AEGON players including Ross Hutchins, Colin Fleming, Laura Robson and Heather Watson. For further information, please visit aegontennis.co.uk