This despicable rag landed on my desk as a brutal reminder that this Friday I shall be doing the hitherto unspeakable for charity: wearing the shirt of Manchester City. To work. All day.

I’ve been a United fan since I learned to walk. My granddad hated them, so I had to follow them. I was at the Trafalgar Square fountains in 99 minutes after the last-gasp clinching of The Glorious Treble. Practically each season I revel as Our Trophy once more returns to Old Trafford as the supposed competition gradually falls away in the league. I observed smugly as John Terry missed his penalty in Moscow two years ago and Giggsy put the seal on it.

Meanwhile, on the other side of the city of Manchester, the blue half continues to wallow in its own self pity, the arabian swagbag doing little more than funding the short-lived arrivals of past-it posterboys. Apart from Tevez of course, we wanted him.

So as part of Sport Relief 2010′s Shirt of Hurt challenge it is with heavy yet charitable heart that I have agreed to don the filthy blue muck this Friday. Clients and colleagues, I apologise in advance. You too do not deserve to be subjected to this.

The flipside is that former client, former journalist and comrade Paul Maher at Positive Marketing, a lifelong fan of the City Scum, has agreed to wear the Shirt of the Champions on Friday as part of this arrangement. That way I do not suffer alone. Although I pity the poor postman who delivered it to him yesterday.

So as Ray Winstone has done it, I’m sure I can tough it out. If you want to donate to mark my humilation, please go back to that link above. All for a very good cause.

More on Friday, providing I don’t call in sick.