St. John's carried the Big East banner most of the season, but it's Xavier that will represent the conference in a regional final for the second straight year.
The No. 3 regional seed Musketeers beat Oklahoma 11-0 on Sunday afternoon to set up a meeting with No. 7 national seed Louisville at night.
The Musketeers knocked out Kyle Tyler during an eight-run first inning. Rylan Bannon was 4 for 4 with a home run and three RBIs, and left-hander Trent Astle and Jason Hall combined on the shutout, with Astle working a season-high eight innings.
It was an ugly ending for the Big 12's Sooners.