 Complete the following phrase:  He turned professional in 1970. His first professional match was in March 1971, against Alex Higgins in the first qualifying round of the 1972 World Snooker Championship, resulting in a 411 loss. Gross had not played competitively for several years before the match, and admitted that he was out of practice and played very poorly. Gross next three professional competitions all ended with defeats in his first match. In the 1973 World Snooker Championship, Gross lost 29 to Perrie Mans, and at the 1973 Norwich Union Open he was eliminated 24 by Barron. At the 