Now that the New York Yankees' Mariano Rivera has retired, the band Metallica doesn't have much to do.

Rivera's entrance music whenever he'd come in to pitch was Metallica's hit "Enter Sandman" from its 1991 album, "Metallica." But since he called it quits last season, there's no need for the band at Yankee Stadium and they've been just kind of sitting around -- as this ESPN "SportsCenter" promo clearly shows.

ESPN "SportsCenter" promo with Metallica

New York Yankees' Mariano Rivera's last entrance at Yankee Stadium