William R. Saar of East Rockaway wore two uniforms — one with a shiny badge on the front and one with a number on the back. He was both a New York City cop and a National Basketball Association referee, but he often wore both sets of digs on the same day as he raced from one pulse-racing gig to the other. Saar, who made calls on the basketball courts for more than two decades for some of the best who played the game — Kareem Abdul-Jabbar, Julius Erving, Magic Johnson, Michael Jordan and Larry Bird — died Dec. 24 after a long battle with cancer. He was 87.