Like he did Monday, Manny Machado looked over his shoulder as Tommy Pham’s first-inning rocket sailed deep over the wall in left field. Like he did Monday, the Padres’ third baseman erased it quickly, following Austin Nola’s leadoff single with a homer to left in the bottom of the inning. “I’ve been on the other side of it quite often,” Padres manager Bob Melvin said after a 6-2 win over the Reds. “He’s just a big-time player. He knows the moment.” Machado’s blast on the heels of an old friend wasn’t all that was familiar Tuesday. The starting pitcher, Joe Musgrove, turned in a quality start. …