PARIS (AP) — It's an oft-cited and oft-updated stat in men's tennis: The so-called Big 4 — Roger Federer, Rafael Nadal, Novak Djokovic and Andy Murray — have won 47 of the past 52 Grand Slam titles, a run of dominance that began in 2005. Add in Stan Wawrinka to make it a Big 5, and the number becomes 50 of 52. And the frequently repeated accompanying questions are: How much longer can these guys continue to dominate the sport?Read more on NewsOK.com