“All four of those are on grass, whereas I have to play some on a hard court!”
Roger Federer (1981) Swiss tennis player
Humorously explaining why it is more difficult for him to win all four grand slams in Tennis than it is for Tiger Woods to win in Golf. http://thestar.com.my/news/story.asp?file=/2007/2/5/apworld/20070205075903&sec=apworld