They won. 5-3
It is double elimination in each regional. They will play the loser of the Fullerton / Stanford game tonight. One of those teams win the regional undefeated and either Illinois or the loser of the CSF/Stan game will advance also by only losing once.
The Illinois would have to win 2 against the undefeated team to play next week.
Really long road to go. But, if somehow they can, there are a lot of #1s going down, so next set of super regionals would be less tough than if all the #1s rolled through.