Aimone Barabino, Danny McClintick and Chancellor Ramirez each scored two goals to lead the Bruins.
The Bruins will face No. 6 UC Santa Barbara on Nov. 29 at 1:30 p.m. in the quarterfinals.
Freshman Ryder Roberts scored the game-winning goal to beat the buzzer in the second OT period.
MPSF title implications on the line for the Bruins as they host the Trojans on Nov. 21 at 7:30 p.m.
Limited seating for UCLA students will be available on a first-come, first-serve basis.
UCLA posted a 10-7 win on "Senior Day" over No. 6 UC Santa Barbara on Sunday afternoon.
Senior Lucas Reynolds, junior Paul Reynolds and sophomore Danny McClintick each scored two goals.
UCLA travels to Pepperdine on Nov. 16 and returns home to host UCSB on "Senior Day" on Nov. 17.
Lucas Reynolds and Paul Reynolds each scored two goals against the 49ers.
Senior Paul Pickell and the Bruins look to extend their league-leading five-game winning streak.
Freshman Ryder Roberts scored a career-high four goals in the win over the Eagles.
Cristiano Mirarchi completes a hat trick in the win over the Golden Bears.