The 50 is effectively an 85mm class (35mm equivalent) - it has a large open aperture but most sports are telephoto (you are on the sidelines) the 55 - 200 (or do you mean the 55 - 250 and F 5.6 at 250) would seem a batter choice - with so many pixels on a small sensor you need to try to limit ASA to 400 to keep from getting noise but your depth of field at 200 / 250 isn't very great so you have a struggle there
NOTE: Turn Image Stabilization OFF when shooting action - otherwise it tries to follow the moving object blurring everything
Also note: Digital cameras are, by their very nature, daylight cameras, they do not like night time light levels, have issues autofocusing, etc.
For portraits the 50 1.8 would seem a good choice (85mm class is called "Head and Shoulders" for the shot you get from 6 foot); and F 1.8 gives you lots of light and low depth of field that you want in a portrait
If buying new Abe's of Maine has these just under $100 with shipping included; used I have seen %50 and 60 occasionally on craigslist in larger cities but act fast because others will scoop it up at that price
If you can use preset (no AF, No IS, No Aperture set by camera) you can get even better glass by looking at used Pentax / M42 thread lenses and a $5 adapter (
ebay) - Pentax F 1.4's go around $100 (even 40 years old!) but Mamiya goes for less than $50 and is just as good if not better; F 1.8's go cheaper - and (here's a dumb thing) often the camera and lens is cheaper than the lens; I once got a Mamiya 1000 DTL (working) with the F 1.4 for $30 - craigslist or
ebay
Personally, unless you have a lot of money try using what you have first
Also consider the old standard portrait lens was roughly 100 / 105 mm; you can get an 85mm F 1.8 that is Macro-focusing (if you have the money) and have that macro ability as well