New York, NY - Earlier this afternoon, top-rated middleweight contender and former two-time world title challenger Matthew "Mack The Knife" Macklin held an open media workout at The Trinity Boxing Club in downtown Manhattan ahead of his much anticipated world championship clash this SATURDAY, JUNE 29, 2013 against WBA/IBO Middleweight World Champion Gennady "GGG" Golovkin at the MGM Grand Theater at Foxwoods Resort Casino in Mashantucket, Connecticut. Photos by Damien Acevedo/BoxingScene.com.