On Tuesday, world boxing lost one of its marquee events as Canelo Alvarez was forced to withdraw from his highly anticipated rematch with Gennady Golovkin amid a succession of failed drugs tests.The pair were due to meet on May 5 in Las Vegas in a rematch of a controversial draw that many spectators scored as a Golovkin victory.In preparation for this fight, Alvarez twice tested positive for the banned performance-enhancing drug clenbuterol during testing by the Voluntary Anti-Doping Association.Pending a hearing on April 18, the Mexican fighter could be banned for up to a year, however, as it is his first offence, and if he cooperates with the commission, this could be reduced to just six months.That would allow for the rematch with Golovkin to be rescheduled on the Mexican Independence Day weekend in mid-September, which is when they had their fight last year.Statements from Golovkin's camp, however, seem to suggest that their fighter isn't keen to wait that long to get back in the ring, re-iterating the fact that Golovkin will be in action on May 5. Among the potential match-ups for Golovkin is current WBO middleweight champion Billy Joe Saunders.Saunders himself has had to postpone his own title defense due to a broken hand with a fight against Martin Murray at the 02 scheduled for June 23. Saunders' promoter Frank Warren has suggested, however, that if his fighter had a shot at a unification bout with Golovkin, he could be ready sooner than that date.Warren told the Daily Mail: "That was the only date in June available at that arena. Although Billy Joe can't recover in time for May 5, he could go as early as the first or second Saturday in June."I am making a huge offer for Gennady to come to a football ground in London. Otherwise we are just as happy to go to Las Vegas, where Golovkin is keen to headline for the first time in his career."The T-Mobile Area in Vegas are already refunding the high-price tickets for Canelo-Golovkin. Their problem now is that the date coincides with a Mexican national holiday and most of those expensive seats have been taken by the thousands who come across the southern border to celebrate."It might be wiser for Gennady to take a slightly smaller arena in June and fill it with Billy Joe, who really believes he has a great chance of winning that fight."Saunders may not be ready for a fight on Cinco De Mayo, but Golovkin will surely be interested in the opportunity to add another belt to his collection.

As for Alavarez, he hasn't tested positive for any banned substances in his numerous other tests since February, so it seems likely a lighter sentence may be passed down upon him - freeing him up for another potential September blockbuster.