Pens blank Isles without Crosby, Malkin (AP)

Without superstars Sidney Crosby and Evgeni Malkin, the Pittsburgh Penguins are learning to win games by focusing on defense. The latest evidence came in a 29-save shutout by Marc-Andre Fleury in a 1-0 win over the New York Islanders on Tuesday night. It was Pittsburgh’s fifth win in its past six games — all without Crosby — and second in three games with both Crosby and Malkin out due to…