Cristian Techera’s deflected effort was cleared off the line on nine minutes, and the visitors continued to create openings in the game.
However, it was the hosts who went ahead on 55 minutes when Juan Manuel Martinez kept his nerve and fired past the keeper into the far corner.
RSL has a shot of their own cleared off the line near the end when Joao Plata’s effort was scrambled off the line by Tim Parker, but the hosts went on to claim the three points.
Visitors start the game strongly
Salt Lake came into the game at Rio Tinto with an 100% home record this season, however, it was the Whitecaps who threatened to open the scoring in the opening exchanges.
Octavio Rivero latched onto a ball over the top, and after coasting into the area, he fired across goal and just wide of the far post.
Just four minutes later the visitors went close once more, Nick Rimando got a hand to Techera’s shot, which took the sting out of the ball, and Aaron Maund headed away bravely to deny the opening goal.
More chances go begging for Vancouver
Rivero found himself in the same position as his first chance of the game on 29 minutes, it was Nicolas Mazquida with a neat ball over the top, but the forward fired straight at the keeper.
Chances were few and far between for the rest of the first-half, but the hosts continued to soak up the pressure which was being applied by their opponents.
However, Vancouver went close once more five minutes after the break, when Rivero dispossessed Justen Glad on the edge of his own area.
The forward found the feet of Mezquida, whose brilliant strike was met with an equally brilliant save from Rimando.
RSL take full advanatge of counter attack
RSL were living dangerously and somehow were holding on in the game, but the Whitecaps were left with their head in their hands when the deadlock was broken.
After a swift break forward, Plata found Martinez in the area, and after the nifty forward cut back inside, he rifled his shot home from close range.
Martinez was pulling out all the stops and the goal appeared to give him more confidence, especially when he skipped past two players skilfully.
He then was allowed acres of space to run with the ball, and when no player close him down, Martinez decided to shot, and David Ousted was called upon to parry the shot over the bar.
Hosts go close late, but hold on for win
There was time for one more chance in the game, and it fell to RSL, who came very close to sealing the victory with a second goal.
Jordan Allen played a through ball to Plata, whose shot, which rolled under the keeper, was cleared off the line in the knick of time by Parker.
The Whitecaps haven’t made the best of starts to the new season and their next game sees FC Dallas travel to BC Place next Sunday, while Salt Lake travel to the StubHub Center to face the stars of LA Galaxy on the same day.