Rapid City entered the contest riding a three-game winning streak.
But the Fuel scored two unanswered goals in the final frame to beat the Rush, 3-2.
Spencer Watson scored twice for Indy and Matt Marcinew scored the game winning goal with 1:54 left in regulation.
Eric Israel led the Rush with one goal and one assist.
Dave Tendeck suffered the loss for Rapid City, stopping 21 of 24 shots.
The Rush are currently chasing Utah for the fourth and final playoff spot in the Western Conference.
The Grizzlies defeated the Allen Americans on Saturday in overtime, 2-1.
Despite losing to Utah, the Americans clinched a spot in the playoffs.
KBHB Radio - Indy strikes late to get game three win over the Rush
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Rapid City Rush defeat Indy to win their third straight
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