Kreilach also assisted Rubio Rubin's eventual winner in the 57th minute and Anderson Julio's late insurance tally as Salt Lake (12-11-6, 42 points) won its seventh consecutive home match to maintain its grip on sixth place in the race for seven Western Conference playoff spots.
The Rapids (14-6-9, 51 points) had won the previous four such trophies, awarded to the winner of the regular season series between these rivals.
Younes Namli pulled a goal back in the 73rd minute for Colorado on a ferocious half-volley that redirected off Kreilach on its way past Ochoa.
Michael Barrios and Jonathan Lewis also both struck the goal frame moments before Namli's goal as the Rapids missed a chance to clinch a playoff berth and move into second in the West above Kansas City.
Kreilach gave RSL the lead in the 13th minute off Aaron Herrera's 10th assist from his right back position.
After using his chest to control a pass, Herrera curled in an early cross toward the near post, where Andrew Brody flubbed his header attempt. But Kreilach was there at the opposite post to guide the skipping service past goalkeeper William Yarbrough.
The hosts doubled the lead 12 minutes after halftime when Kreilach took down a loose ball and quickly spotted Rubin in the penalty area with a throughball.
Rubin angled his run to beat defender Lalas Abubakar, then drove a low finish from close range past Yarbrough.
Barrios and Namli entered moments after the goal, and the Rapids immediately looked more threatening.
But once Namli broke through, RSL did better to limit the chances for an equalizer and looked the more likely to score late.