DeNato, a junior left-hander, struck out eight and walked three in the 136-pitch effort.
The Hoosiers gave him a 1-0 advantage in the first inning on Kyle Schwarber's RBI single.
They made it 2-0 in the third with a one-out, run-scoring single from Michael Basil.
The victory earned Indiana a date with Mississippi State in Sunday's winners' bracket game. The Bulldogs bested Oregon State 5-4 in Saturday's first game.
Cole Sturgeon supplied two hits for the Cardinals, who will take on the Beavers Monday in an elimination game.