After two fans dressed as Teenage Mutant Ninja Turtles sat right behind home plate in the Bronx on Opening Day, visible from the center-field camera on every pitch, four fans — two dressed like Katy Perry's sharks from her Super Bowl performance and two in turquoise unicorn costumes — sat in the second row Wednesday night, though they were just off camera toward the third-base side. All four were winners of the contest put forth by HBO's "Last Week Tonight" hosted by comedian John Oliver.