Guess? That ain't no guess! That's what it's gonna be.
5 seconds sound clip from the The Waterboy (1998) movie soundboard.
You can hear this line at 01:16:06 in the Blu-ray version of the movie.
Quote context
[...]
- I'm with Vicki Vallencourt, who's taking over Bobby Boucher's water duties for this important game.
- I'm not takin' over. I'm just tryin' not to screw up too bad.
- Well, let me ask you this. What's your prediction for the rest of this game?
- Mud Dogs are gonna win, 30-27.
- That's very interesting. How'd you come up with that guess?
- Guess? That ain't no guess! That's what it's gonna be.
- All right. Meaney! Where's Meaney? Meaney?
- All right, get in there and see if that waterboy can stop you. Go, go, go, go!
[...]