The first AMA Supercross Triple Crown event of the season saw Team Honda HRC rider Chase Sexton finish third overall in Glendale, Arizona, helped by a first-place result in the last of three 450SX races, while teammate Ken Roczen finished fifth overall. In the 250SX West class, Hunter Lawrence took his first win of the season with consistent 2-1-2 finishes.

Roczen ran in second early in the first 450SX race, but he slipped two positions before the finish. Meanwhile, Sexton suffered a couple of tip-overs and turned in an 11th-place result. Sexton and Roczen had their CRF450R race machines in the top five for the majority of the 12-minute-plus-one-lap second race. Sexton made smart passes for a third-place finish, while Roczen was sixth at the finish. Sexton secured the holeshot in the final race and built a four-second lead before eventually reaching the checkered flag with a 2.5-second margin. Roczen suffered a poor start and climbed to seventh by the finish.

Lawrence was impressive all day in the 250SX West class, topping daytime qualifying aboard his CRF250R and charging hard in the night program. The young Australian battled over second in the first race, eventually securing the position. In the second race, he avoided a dramatic incident involving Vince Friese and points-leader Christian Craig to take the win. The final race saw Lawrence complete lap one in third and then race to a runner-up finish, which was enough for the overall victory.