Nathan MacKinnon scored twice in a three-point performance and goaltender Mackenzie Blackwood won his Stanley Cup playoffs debut as the visiting Colorado Avalanche claimed a 5-1 victory over the Dallas Stars on Saturday to open their series.Artturi Lehkonen, Devon Toews and Charlie Coyle also scored for the Avalanche to begin the Western Conference first-round series.Blackwood made 23 saves and Logan O’Connor collected a pair of assists.Roope Hintz replied for Dallas, which opened the playoffs without its top defenseman, Miro Heiskanen, and its leading goal scorer in the regular season, Jason Robertson.Jake Oettinger stopped 19 shots for the Stars, who have lost eight consecutive series-opening games.Dallas, which finished four points ahead of Colorado to claim second place in the Central Division, also lost its final seven regular-season games (0-5-2).Game 2 of the best-of-seven series will be Monday in Dallas.Lehkonen opened the scoring at 9:30 of the second period with a lucky goal. His first shot off the rush was stopped, but he fell while heading to the net for the rebound and the puck went off his skate and into the cage.
