HOW DO YOU DO THIS HIGH-FLYER FREESTYLE DUNK?

http://www.youtube.com/watch?v=k7XRWOfJ5ZA

im referring to dunk number 1..the last one where t-mac smashes one over dirk.

ive done pretty much every dunk in this game (i think), i ve jumped over ppl and all that...

but i cant find the freestyle combo to do that one!! the cpu does it all the time haha

what 'criteria' is needed? ie: one-on one with big man near the basket, what do you tap/hold etc

THANKS

to do that its (PC) 3 Button (XBOX) A Button (PS2) X Button but u have to hold it while someones under the basket.