The Monstars stole the talent from the NBA players.
9 seconds sound clip from the Space Jam movie soundboard.
You can hear this line at 00:58:25 in the Blu-ray version of the movie.
Quote context
[...]
- Yeah, right. That's gonna help us.
- Looks like Stan just had a close encounter with a bug-zapper.
- The Monstars stole the talent from the NBA players.
- So that's what happened to those guys.
- I think we should qui... Forfeit.
- Listen, I didn't get dragged down here just to get my butt whipped by a bunch of ugly Monstars.
[...]