Los Angeles stayed within three games of St. Louis for the National League's second wild card berth.
Kershaw (13-9) walked two and gave up five hits. After throwing 113 pitches, he was not given a chance to pick up what could have been his third complete game and third shutout of the season.
He was staked to a four-run lead in the second inning when Andre Ethier delivered an RBI double and Victorino hit his 11th homer of the season.
Bobby Abreu contributed a two-run blast in the eighth.
Jeff Francis (5-7) was victimized for five runs on six hits in four innings to take the loss.