The London 2012 will be all about some of the biggest rivalries in sports, and MSN Sports is here to point out the fiercest ones for you to keep an eye on.
Veronica Campbell-Brown Vs Allyson Felix (Athletics)
Jamaica's Veronica Campbell-Brown pipped the United States' Allyson Felix to the post to win the 200m event at the Beijing Olympics. Felix knows that she will have to duplicate the gold-medal winning effort she put in at the 2007 World Championships in Osaka (beating Campbell-Brown), if she wants to win the yellow metal. But on current form, this battle is Campbell-Brown's to lose.