DALLAS — Alex Tanguay scored the winning goal early in the third period, and Semyon Varlamov made it stand up for the Colorado Avalanche in a 4-3 victory over the Dallas Stars on Monday night that ended the Stars’ three-game winning streak.Colorado led twice, but both times Tyler Seguin scored to tie the game for Dallas. Seguin, the Stars’ leader with 23 goals, had not scored in 13 games. He also had an assist on Jamie Benn’s first-period goal, and Seguin finished the season series against the Avalanche with four goals and four assists in five games.Alex Goligoski assisted twice for Dallas, and he now has seven assists in the last four games and 10 in the last eight.Varlamov made 41 saves, including two on Seguin during a third-period power play with the score 4-3. Varlamov has four consecutive wins against Dallas.Colorado’s Nathan MacKinnon scored on the game’s first shot. Jamie McGinn also scored in the first period, and Paul Stastny connected on a power play in the second.Tanguay’s fourth of the season made it 4-3 at 4:13 of the third. Maxime Talbot and Gabriel Landeskog had two assists apiece for the Avalanche, which won two of three games on a road trip that ended Monday. The Stars had won their previous three games.MacKinnon scored after a shot was knocked down in front. The puck went to him just to the left of the goal, and he tapped in a shot before goalie Kari Lehtonen could slide across to that side.Lehtonen had allowed only one goal in 67 shots during the three previous games.Seguin’s first second-period score that tied the game 2-2 extended Dallas’ streak to eight games with a power-play goal.Even so, the Avalanche regained the lead on Stastny’s power-play goal at 17:57 of the second. The Stars had successfully killed 16 consecutive penalties before that.