Ciman, the last player cut from the Belgian national team as it prepared for the World Cup, sent a free kick from 40 yards out just inside the post to open the scoring in the fourth minute.
Adama Diomande doubled the advantage in the eighth. Benny Feilhaber dropped it to Lee Nguyen at the top of the box, and he found Diomande for the finish from the center of the area.
Tyler Miller, who had allowed 10 combined goals in the last five games, had one save in his fifth shutout of the season for LAFC.
Columbus (7-5-6) has lost two in a row after a nine-game unbeaten streak
LAFC (8-4-3) is unbeaten at home (three wins, three ties) this season.
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