Andre Agassi and Pete Sampras will add to their long history at Madison Square Garden. But where do they rank among the best of tennis' rivalries?
Just because Rafael Nadal's Australian Open run ended in heartache doesn't mean that Andy Murray now has a free pass to the final.
In 2007, tennis' upper echelons dealt with match-fixing allegations, a bizarre retirement and a possible poisoning. Meanwhile, Great Britain's Lawn Tennis Association had its own mini-crises.