Jared Brownridge scored back-to-back to spark a 10-0 run that gave Santa Clara (3-7) a 69-59 lead with 1:37 left. He finished with 25 points, the first time in three games that he reached double digits.
Devon Marshall's jumper for Pacific Union tied it at 59 with 5:08 to play. The Pioneers missed their next four field-goal attempts while Santa Clara pulled away.
Pacific Union had the lead four times in the first half, but the Broncos never trailed after scoring the last four of the period to lead 38-34 at intermission.
Mike Hill was 8 of 16 from 3-point range and scored 34 to lead Pacific Union.
Kratch pulled down 10 offensive rebounds and had his third double-double in as many games.