The Tritons also guaranteed the WWPA's automatic bid to the NCAA Championships in Michigan, May 13-15. The win marks the first time UCSD (17-18) has defeated a ranked opponent this season.
Sarah Lizotte led all scorers with four goals while Hanalei Crowell and Jessica Tran each recorded a hat trick. Allie Taylor recorded seven saves in goal. Neither team led by more than a goal until the final quarter.
The Tritons spoiled the Lions' quest for a third consecutive championship. LMU (26-9) won the title in 2009 and then went on to take down UCSD in the 2010 edition.
"Beating LMU to win this championship was really special," said UCSD head coach Brad Kreutzkamp. "They have been so dominant and had a 37-match conference winning streak coming in. It was very sweet to be able to break that run."
The Lions led 9-7 and 10-8 in the final stanza, but UCSD scored three unanswered to take an 11-10 lead.
"When we tied it at 10 with two and a half minutes to go, I noticed LMU's demeanor going backward and out team was getting more and more excited," said Kreutzkamp. "They really started to believe they could do it."
Kimberly Benedetti evened the score for LMU, but Crowell scored the game-winner with 1:59 to play and Katherine Biehle added another on their way to a two-goal victory.
MVP: Hanalei Crowell (Sr., DR) - UC San Diego
Hanalei Crowell (Sr., DR) - UC San Diego
Kirsten Bates (Jr., 2M) - UC San Diego
Sarah Lizotte (Fr., UTL) - UC San Diego
Kimberly Benedetti (Jr., 2M) - LMU
Erin Manke (So., DR) - LMU
Wren White (Sr., GK) - Santa Clara
Whitney Allen (Sr., DR) - Santa Clara
Claire Pierce (So., UTL) - Cal State East Bay
Natalie Peng (Jr., UTL) - UC San Diego
Casey Flacks (Jr., UTL) - LMU
Jayme Pekarske (Jr., GK) - Cal State East Bay
Ali Pavlik (Sr., DR) - Colorado State
Jessica Stansfield (Fr., UTL) - Sonoma States
Sam Shead (So., 2M) - Cal State Bakersfield
Chloe McRae (Sr., CTR) - Cal State Monterey Bay
Bryanna Burns (Sr., GK) - Cal State San Bernardino