Girl's Basketball--New Shooter here...Help and Comments please!

I have a new Sony A-57 I am trying to shoot girl's basketball pics with.  I've done some research and know the recommended lens is a 70-200mm f2.8, but that's a little out of the budget now.  I bought two Minolta lens, the beercan and the 50mm 1.7 (for very little money) that I have tried.  Here's what I got out of the beercan:

Minolta 70-200 F4, using Automatic Sports Action Mode setting

Many of the shots using the Automatic Sports mode did not freeze the action (shutter speeds ended up around 1/250 on some).  I've gotten much better shots with the 50mm 1.7, using Shutter priority at 1/400 and ISO set at 1600, for example:

Minolta 50 mm, Shutter Priority at 1/400, ISO 1600 and this one:

Minolta 50mm f1.7, Shutter priority 1/400 and ISO 1600

Keep in mind I am a new shooter and am just learning the basics.  Are there any other settings I should attempt to get better shots with the equipment I have?  Would an 85mm prime lens be too long for these shots from the end of the court?  Are there any other inexpensive Minolta lenses that might take better shots than this one?  All help, criticism and comments are greatly welcomed!  Thanks!