Tennis superstar Daniil Medvedev had an unforgettable performance on the court at the Monte-Carlo Masters -- and by "performance," we mean an epic meltdown for the ages. The Russian athlete suffered the first double bagel loss of his career against Matteo Berrettini on Wednesday ... and during the blowout defeat, he took his frustrations out on his racket. Medvedev slammed his equipment on the ground not once, not twice ... but seven times in a row before throwing it in the trash in the second