DENVER—First Julio Urías. Now Walker Buehler. That’s back-to-back off outings from key cogs in a Los Angeles rotation that boasted the best ERA in baseball. Logging too many innings? Wearing down? Dodgers manager Dave Roberts had a simpler explanation: “All guys have some bit of fatigue right now,” he said. Sam Hilliard lined a three-run homer, C.J. Cron had four hits and the Colorado Rockies snapped a five-game skid at Coors Field by beating the NL West title-chasing Dodgers 10-5 on Wednesday night. The Dodgers fell two games behind division-leading San Francisco, which beat San Diego 8-6. This had all the makings of a pitchers’ duel with All-Stars Buehler and Germán Márquez on the mound. Instead, it was anything but, as the teams combined for 19 hits, including three homers and even a two-run double from Márquez that chased his counterpart from the game. “My job is to set the …