Lenses: which would you do?

ok so I've been thinking about this for a while and I'm torn as to which way to go, so I figured id see what some of you would do, or what you think would be the better thing to do.

Im trying to decide what to do for this coming semester at college for shooting sports. Ill be shooting basketball, baseball, football, and some hockey on my own time. Im torn between to options. Either keep my sigma 70-200 and get a 300 2.8 non IS, or get a 100-400 again to use for the baseball and football (sold mine because I didn't use it much at the time) and upgrade my sigma to an 70-200 IS I. In the end both options will cost me about the same, but I'm having trouble deciding which way to go.

If you were me, which route would you go?

Sigma 120-300mm f/2.8 if you have $3200. It should be great for football and baseball. I know nothing about it but would love to try one.

More realistic would be a 100-400 if the games will be during the day or the fields have outstanding lighting for night play. The 70-200 is extremely short for baseball and football unless you have very close access to the action.

The Canon 70-300mm f/4-5.6 L IS lens is something else to consider if you weren't happy with the 100-400mm lens.

Basically, you need more than one lens to cover these sports. A tele-zoom for the baseball and football, and a fast zoom, or prime for indoor hockey and basketball. The lighting in basketball courts and hockey rinks, necessitates at least f/2.8, with fast focus. Baseball and football need fast focus, but due to better lighting(usually), you can get away with f/4-5.6..depending on the time of day/clouds, etc.

The 100-400, Sigma 120-300 OS(+ TC), Sigma 150-500 OS, or a good 70-200/2.8 with TC's for outdoors. A 70-200/2.8 and or a fast prime or 2(85/1.8 or 135/2) for indoors.

Notice the 70-200/2.8 in both categories, so that might suffice for all your needs, with a TC, and/or some judicious cropping.

ya ill definitely have a 2.8 either way, and will be buying a longer lens one way or the other. Just hung up on which I should get. I can't really complain about my sigma, its served me well, but I've always wanted to upgrade to the canon IS. at the same time I liked my 100-400 and wouldnt mind getting one again, but id rather get a 300 2.8. just having trouble deciding which way to go. One way I have 2.8 all around, the other I have IS all around... though at the higher shutter speeds I know its less needed than at slower. I've got a few weeks before I absolutely have to decide, so figured id see what you all thought.

Of course a 300/2.8 would be sweet for field sports, but spending all your money on just one focal length( 3 with TC's) is a tough decision to make.

i'd go for the suggested 120-300f2.8 OS...you're looking at $2,000+ for the old 300mm...you sell your 70-200mm...and you're close to the price...

if I was going to spend over 3k for a lens, I think id have to go for the 300 2.8 IS. but thats a bit out of my range, which is what brought me to the two options I was considering... looks like if got more thinking to do