After SFSU scored the opening goal in the 50th minute, second half scores from Tritons Shelby Wong, Ellen Wilson, and Courtney Capobianco helped UCSD (15-2-3) move through to the second round for the third consecutive year.
The Tritons move on to face West Sub-Regional host and No. 2 seed BYU-Hawaii at 9:00 p.m. PST on Saturday night. The Seasiders are 14-1-2 on the season and earned a bye in the tournament's opening round.
Kara Cunningham gave the Gators a 1-0 lead in the 50th minute, slotting home a goal off an assist from Carly Bliss. Less than two minutes later, Sarah McTigue would break away from two defenders, cutting the ball along the endline towards goal before passing it off to Annette Ilg. The senior forward cracked a shot but the rebound dropped to Wong's foot, who easily slid in the ball past the keeper.
"We came out of halftime going at them," Wong said. "Getting down a goal was disheartening, but we had a lot of time left and we came right back at them. We shouldn't have to go down a goal to step it up, but I think it showed our character."
In the 65th minute, a Triton corner kick would fall to the foot of Ilg inside the penalty area. Ilg would pick her head up and find an open Wilson, who collected the ball and finished easily with her next touch.
UCSD's insurance goal would come in the 84th minute, as Gator goalie Annicia Jones was unable to corral a Triton shot attempt, leaving the rebound for Capobianco, who pounded home the third and final goal of the match.
"The starters all did a good job but tonight we got a lot of help off the bench. When we went there, the level of play didn't dip and, in fact, raised the game," UCSD head coach Brian McManus said.
The win marked McManus' 400th career victory at UCSD. He is now 400-60-34 in 24 seasons at the helm of UCSD women's soccer.
BYU-Hawaii enters Saturday's matchup having won 10 of its last 11 contests. The Seasiders, who were receiving votes in the final regular season NSCAA Division II Coaches Poll, earned an NCAA Tournament automatic bid after winning the Pacific West Conference title with a 12-1-1 league record.