The Horned Frogs (45-12) advanced to play N.C. State, which beat TCU 5-4 on Saturday night.
Skoug, a freshman catcher, has a team-high seven homers. Connor Wanhanen went 3 for 5 with two RBIs and Nolan Brown was 3 for 5 with two doubles and a RBI for TCU.
Frogs starter Brian Howard left during the fifth inning due to injury. He had been pitching a two-hitter with three strikeouts. The relief staff combined to hold Stony Brook to two hits.
Teddy Rodliff had a short start for Stony Brook (35-16-1), going just 1 1-3 innings, allowing four hits and two runs. Bobby Honeyman scored two of the Seawolves' three runs.