The Clash of Times event featuring current World No. 1 and 11-time Grand Slam title winner Roger Federer in a challenge match against all-time great Pete Sampras. 14-time Grand Slam title winner Sampras would make a come back to professional tennis challenging the supremacy of Federer on the historic match and some referring to it as the greatest tennis match-up in history. Two of the greatest tennis players ever will battle for pride and dominance over the past two decades in the sport’s history.