New York City FC ask New York Red Bulls fans to switch allegiances and get a free shirt

When you think of the world's great football rivalries, what springs to mind?

Barcelona and Real Madrid? Manchester United and Liverpool? Maybe even Boca Juniors and River Plate? The chances are you probably *don't* think of New York Red Bulls and New York City FC. But make no mistake about it, although it may be one of football's (soccer's) newest derbies, fans of the two clubs don't seem to get on that well. Last year it kicked *right* off between the two sets of supporters. Just listen to the sheer hatred in the 'Who are ya?' chants heard in the video below.... https://twitter.com/RobHarris/status/630488065014951940?ref_src=twsrc%5Etfw With the two sides set to meet again in the coming days as part of Major League Soccer's 'Rivalry Week', New York City FC have taken an unusual step in a bid to get an edge over their new, more established rivals. https://twitter.com/nycfc/status/733393033123799040 Yes that's right. They're asking rival fans to hand in their Red Bulls' shirt (and with that their allegiance to their club) in favour of a brand new New York City FC one. Only in America, eh? Red Bulls fans weren't going to take this lying down though... https://twitter.com/pete_scanlon/status/733398557735129088 https://twitter.com/Jummper_/status/733395220784644096 https://twitter.com/CBH1970/status/733408091505483776