The sense that this was something different was obvious in the moments when Fletcher's voice cracked as he spoke. The emotion was clear. He admitted later that he had opened up more about the experience of having ulcerative colitis than he had ever done publicly before.
Fletcher sat beside the former England rugby flanker Lewis Moody, another top-class sportsman afflicted by the serious bowl condition, and Alex McLeish's son Jon, another sufferer whose idea it was to launch United For Colitis, an initiative to raise awareness and funds. A gala dinner has been arranged and Sir Alex Ferguson, David Moyes, Gordon Strachan and most of Fletcher's United team-mates will attend.
To listen to Fletcher and Moody was to gain an insight into what they and all other sufferers have to live with. Moody spoke of how being "two or three feet from a toilet can sometimes be too far", of how he once lost 10 kilogrammes of weight in a week, of how he used to live a 40-minute drive from his training ground but had to move much closer because of the frequent toilet stops. Once, he had to rush into a pub at 8.30 in the morning just to use its toilet, only for the cleaners to inadvertently lock him in.
These two great sportsmen, side by side, told their stories of this cruel condition with candour and good humour. Fletcher recalled watching last year's England-Scotland game in "a bit of a blur" in hospital having had surgery the previous day. "I was heavily sedated trying to watch that game and struggling to keep my eyes open," he said. "It proved very difficult but I did manage to open them when Kenny [Miller] scored, which was good!"
There was levity and there was gravity. Ulcerative colitis is an unforgiving condition. "It can mean running to the toilet anywhere between 10, 20 and 30 times a day, with not much time to get there and losing a lot of blood in the process," Fletcher said. "Sometimes you are so weak you end up in hospital. I ended up on an IV drip a couple of times.
"I remember when I was first diagnosed I was very blase about it. Looking back now that was very immature. I was a young footballer playing in the Premier League for Manchester United. I felt on top of the world, I felt untouchable. At first my thinking was that it was a small thing and it wouldn't have any impact on my career or life. It wasn't until it came back in 2010 that I started my real battle with it, which ultimately meant I had to have a surgical procedure.
"I have young children and as a dad it was very difficult not to be able to take them to the park and watch them play football. I couldn't do that and it was hard to explain to children so young. I also have a wife and although she did not have to suffer the symptoms it affected her life as well. Her support and that of my mum and dad has played a massive part in my recovery. The love and support from them, and the understanding, are things I will never forget."
The condition is incurable but it can be controlled and managed. No two sufferers have the same experience. Moody used a combination of drugs; Fletcher had surgical treatment. One mercy for both of them was neither of them ever had to run off during a game or training session: only when playing football did Fletcher feel "normal".
It was poignant to hear the Scotland captain talk about the embarrassment sufferers feel and the worry sportsmen have of being tormented by their team-mates.
"I didn't hide it from the manager [Sir Alex Ferguson]," Fletcher said. "He knew fairly quickly. I did keep it back from team-mates and everyone else. I stayed silent until about 2011, 2012. My close family and friends knew but no-one else at the club did.
"I found it difficult making up stories as to why I wasn't at training, or was looking ill or feeling ill or why I was rushing off to the bathroom. I was basically lying to people's faces. Once I made it public knowledge, it was such a relief. It was the best thing I did.
"I was worried about fans, team-mates, the banter, all that stuff. But, I tell you, everyone has been fantastic. The United supporters, away fans, they've been so respectful. My team-mates have been so supportive. I expected more banter. They have been very sympathetic. It's almost a little bit like, 'you're not dying, get on with it, man up!'."
Moody looked a strapping figure of health. Fletcher, too, looked tanned and well. He talked about his present and future in upbeat, buoyant terms.
"I have a set routine for how I live my life. I don't suffer relapses now. I'm not going to have episodes when I am extremely ill or am taken into hospital or can have a breakdown at any moment.
"It seems to be going well. My surgeon was very confident that I would get back to normal life and being a good husband and good dad." Fletcher has also had the deep satisfaction of becoming a role model. "I've had so many letters from mums and dads, from children, about how easy it's made their lives.
"They can go to school and instead of having to explain ulcerative colitis, they can simply say 'I have the same illness that Darren Fletcher has'. Lewis and [fellow sufferer] Steve Redgrave: I drew inspiration from them. Hopefully me adding my name to that list can help people."
n The Charity Gala Dinner is at Old Trafford on Thursday, March 27. For further details, visit unitedforcolitis.co.uk