To be honest, I don't think many people will be bothered about the fight between Broner and Sykes being cancelled as it was going to be a massively one-sided fight in favour of Broner and many people were shocked that Sykes was even chosen to share the ring with the future pound-for-pound contender. I'm not taking anything away from Sykes, he will be massively affected by this and it was a once in a lifetime opportunity for him but in reality he is a domestic fighter at most.
One possible opponent for July 21st is Vincente Escobedo, who was slated to fight Broner in August. He does have a fight this weekend, but if he wins, a two month break should easily be enough for him. Another fighter that everyone wants to see Broner face is WBO lightweight champion Ricky Burns as many people believe that Broner needs to move up a weight division to prove himself. However, this fight is becoming less likely by the day as Burns has been rumoured to be facing domestic rival Kevin Mitchell on July 14th on the undercard of David Haye Vs Dereck Chisora.
Broner's and Khan's opponents are likely to be announced very soon. We'll have more info on what's next for the two young talents very soon.