need some help with white balance for my shots

i have been struggling with getting a good white balance for the basketball gym i shoot in. i have been told that my photos lately have some green in them from a bad WB setting. for this game i recently shot i took a WB reading off a white piece of paper center court and made it a custom WB setting in camera and then used the shot to adjust all the WB in my shots in light room 3. this photo from the other night seems to represent our gym rather well considering our walls really are off white with a pee yellow ceiling, gym was built in 70's. i do not have a fancy monitor so i have never seen the green that was mentioned in the past. can you guys let me know how the colors in the shot look WB wise.

the gym im shooting in has uneven mixed lighting. this shot was taken with my 7D and 50 1.8 at ISO 2500 f2 1/500

thanks in advance. i hope to get some advice and feed back.

The top one appears to be pretty close. The bottom one seems to have a blue tint.
Since you have image editing allowed, I copied the bottom pic, opened in camera raw and set the WB eye dropper on the sock on his right foot. Here's the result.
I had to reduce the size to copy it here, but no other PP work was done.

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Did I miss if you mentioned that you were using auto-WB? Evaluative? Spot? etc.

Shoot in RAW and you will be able to correct this after the fact.
It's a little more work, but once you go through a batch of images and find you need to "cool" them or "warm them", next time you go, under same conditions you can set/adjust the WB ahead of time.

Since these shots indicate thatyou are staying on the player, i'd meter off of the white clothing.

BTW: that first one looks a little warm looking at his shorts, and 2nd a little cool, but an easy fix in DPP or PS.

On auto-WB, you are going to get varying temps because of the different angles, moving around and metering on different things.