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Nearly impossible to say without knowing how close your seats are and how everything is laid out. I would guess if you're in the stands you'll need as much glass as you can take in. Probably the 70-300?
My question back to you would be, what kind of images do you hope to get? Shooting from the stands doesn't usually yield the best action photos. If you're just wanting to "document" the experience I'd suggest a point and shoot or maybe even just using your phone camera. Less hassle and the images can be equally memorable.
Having said that, I am confident that I can take a 400, 120-300, 70-200, 24-70, 50 and a 15 to just about any sporting event and get the kind of coverage I need. That is my entire lens lineup and I can't say I've ever shot any sporting event where I thought "damn, if I only had a different lens." Sure, there are times I'd like to do things with a tilt-shift or other specialty-type lenses, but for sports action that lens line-up should cover just about anything.