Knighton saw the most action in the first half for the Whitecaps (11-13-10), who will face the Los Angeles Galaxy in a one-game knockout-round contest Thursday.
Vancouver had a goal taken away in the 57th minute when Darren Mattocks headed in a free kick. The play was disallowed on a controversial offsides call.
Kyle Reynish only had to make one save for Real Salt Lake (17-11-6), who will play the Seattle Sounders in the first round of the playoffs.
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