 Complete the following phrase:  Many former champions have gone on to play on the world tour such as Alain Robidoux, Kirk Stevens, Bob Chaperon, Jim Wych, Bill Werbeniuk and most notably Cliff Thorburn who won the competition in 1972, 1974, 1975, 1976, 1977 and 2001, eventually going on to become the first player in the modern era from outside the United Kingdom to win the World Snooker Championship in 