According to a report from Ryan Burton at BoxingScene.com, Danny Garcia will be allowed to take a voluntary defense before facing Viktor Postol, his WBC mandatory challenger, which means that as reported earlier, there is a deal in place for Garcia-Postol, but it won't be Danny's next fight.
Garcia (29-0, 17 KO) might not actually find a tougher opponent in his voluntary defense, unless he fights a rematch with Lucas Matthysse, perhaps. There is also the idea that Garcia may take a step aside and then vacate the WBC belt, since he's with Al Haymon, while Postol (26-0, 11 KO) is promoted by Top Rank. The two sides don't get along, to say the least.
Whatever Garcia does next, I'd imagine boxing fans will just be happy if it's a legitimate opponent. Postol is a legitimate opponent, and that's a good fight if/when eventually does happen. The best opponents with the Golden Boy or Haymon teams right now are Matthysse and IBF titleholder Lamont Peterson, who has said he does want to fight Garcia.
A darkhorse candidate could be veteran Humberto Soto, who beat John Molina on September 13, and is currently ranked the No. 5 contender by the WBC, below Postol, Matthysse, Adrien Broner, and Thomas Dulorme.