Baylor led 7-4 after five innings Friday, but Kansas State took its first lead with a four-run sixth.
The Bears retook the lead in the bottom of the eighth when Cal Towey was hit by a pitch with the bases loaded.
But in the top of the ninth, Kansas State's Jon Davis hit a two-run single that gave the Wildcats a lead they wouldn't relinquish.
The Sooners and Wildcats met last weekend in Manhattan, Kan., with KSU taking two of three games in the series. Hill said he hopes Friday's win secured his team a home regional.
“I'd like to toot our horn a little bit for hosting right now,” Hill said. “Big 12 champions, get a couple wins here, we haven't let up any and we have over 40 wins.”