On this week's MMA, Novak Djokovic's retired from the 2019 US Open in his 4th round match against Stan Wawrinka. I recap each and every 4th round match, including wins by Rafael Nadal and Roger Federer. Then, I preview quarterfinal matchups featuring Gael Monfils, Mateo Berrettini, Grigor Dimitrov, Diego Schwartzman. In comment response, I address the US Open crowd and their treatment of Novak Djokovic. Plus, Daniil Medvedev embracing the New York boos.