Anders Dreyer and Amahl Pellegrino scored two goals each to help San Diego FC beat the Portland Timbers 4-0 on Sunday night and win their best-of-3 first-round series in the MLS Cup playoffs. No. 1 seed San Diego plays fourth-seeded Minnesota in the single-game Western Conference semifinals. Pablo Sisniega made his second career playoff start at goalkeeper for the injured CJ dos Santos and had two saves for San Diego.