Team Europe captain Bjorn Borg said he was "proud" of his players after they completed a resounding 14-1 victory over Team World to claim their fourth Laver Cup title in a row, following Andrey Rublev and Alexander Zverev's 6-2, 6(4)-7, 10-3 victory over Reilly Opelka and Denis Shapovalov in their doubles contest in Boston on Sunday.