Waldyr Pereira, also known as Didi (Portuguese pronunciation: [dʒiˈdʒi]; 8 October 1928 – 12 May 2001), was a Brazilian footballer who played as a midfielder or as a forward. He played in three FIFA World Cups (1954, 1958, and 1962), winning the latter two and was awarded the Golden Ball, given to the tournament's best player, for his performance at the 1958 competition.