Robin Van Persie says he has no regrets over rejecting City for United in Manchester.
The Dutch striker, 29, has smashed 13 goals in 19 games since his £22 million summer switch from Arsenal to Old Trafford.
Van Persie, who faces City at the Etihad tomorrow, said: “I made my mind up very quickly and I am coming into work with a big smile on my face every day.
“It is not really work, it is my hobby — I love football.
“But everyone has been so nice to me and I have been having the time of my life here.
“So I don’t regret that — but of course in a derby you have lots of people involved — the fans and the players.
“Everyone is really committed and wants their team to win and we’ll do all we can to win too.”
Victory for United will put them six points clear of neighbours and title holders City at the top of the table.
RVP added: “Anything can happen but that’s the case with us every week.
“We want to stretch our lead and keep our run going.”