If I was primarily shooting sports, even my T3i would've been insufficient, I'd go for 7D and a fast focusing, fast aperture USM lens - just like TeamSpeed.
I used (briefly) Nikon V, which is probably the fastest focusing mirrorless on the market, bar none. The problem is, with it's tiny sensor, it sucks in dim light - noisy as hell.
My Nex 6 is better indoors than my T3i was, but it's mainly due to it being easier to lift shadows without as much color noise (you still get the grain). But it's not a fast action camera. And the choice of E-mount lenses that are fast enough is limited. Now, with a LA-EA2 adapter, which is basically a focusing unit from one of Sony's SLRs, you can use one of their big DSLR lenses, with good speed - but no image stabilization.
Still... for what I shoot, it works fine. For action-heavy shooting, I'd stick with a DSLR. A7/7r lets you do both with same pool of lenses.
This was shot with Sony kit lens 18-55 f3.5-5.6 - as any kit, it's decent but not spectacular. It keeps up well enough with kicks & jumps, especially with a flash. I also have a couple of primes that are faster and probably focus faster as well, but when action is moving around fast in a relatively small space, and you're confined to one place, it's a PITA to use a prime. If I was shooting things like that a lot, I'd get an A-mount lens and used it with an adapter.

IMAGE LINK: http://www.flickr.com …77380157@N06/11271288046/
DSC09115
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BugsDaddy
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