PITTSBURGH (AP) — Thomas Harley and Wyatt Johnston scored third-period goals and the Dallas Stars beat the Pittsburgh Penguins 4-1 on Tuesday. Bryan Rust scored the first goal for Pittsburgh, but Dallas had the next four, as the Stars haven’t lost in regulation yet this season. Jason Robertson, who scored 46 goals last season, scored his first on Tuesday, as did Evgenii Dadonov before third-period goals from Harley and Johnston. Jake Oettinger stopped 38 shots for the Stars, who won their third straight. Penguins John Ludvig, who was making his NHL debut, left in the second period after being briefly knocked unconscious following a collision at center ice. Alex Nedeljkovic made 31 saves.