The Daily Telegraph's Will Greenwood believes Munster's Tomas O'Leary and Biarritz's Dimitri Yachvili hold the key to their Heineken Cup semi-final showdown.
"If you want a clash of styles think McEnroe and Borg. What about Botham and Boycott, or Davis and Higgins? Can anyone doubt the class of these greats? Yet they seem to be diametrically opposite in how they go about achieving their goals.
"On the one side we have people who have been called ice-cool, straight-laced, unimaginative, and even deadly dull. On the other you have explosive, swashbuckling, nerve-jangling, death-defying exponents of their chosen sports, who live on the edge but also get over the line first. It is the beauty of sport that there is no right or wrong way to do things. There is only winning and losing.
In San Sebastian, Spain, we have two contrasting players who hold the key to Biarritz and Munster's Heineken Cup hopes. And while they do not enjoy the personality extremes of the rivals above, they are scrum-halves at opposite ends of rugby's evolutionary road."