Diego Schwartzman, apparently, has a twin...if that twin was an American that was at least 15 inches taller. At the Laver Cup, the world No. 14 introduced his Team World teammate John Isner.

Diego Schwartzman didn't walk away with a win against Rafael Nadal on Thursday at Roland Garos, but he left a resounding impression nonetheless. The world No. 12 won a set off the Spaniard ...