Crunch time on finalizing roster spots is approaching, and the Marlins are weighing all possibilities — inside and outside the organization. Backup catcher is a position that is getting closely watched. And Miguel Olivo, who played with the Marlins in 2006-07, is a strong candidate to return. With Jeff Mathis expected to miss at least the first month with a broken right collarbone, Miami currently has two young, left-handed hitting options — Rob Brantly and Kyle Skipworth. Both are 23-years-old. Brantly, the starter, has 31 games and 100 at-bats of big league experience. Skipworth, a former first-round pick, has yet to have an MLB callup. In recent days, the Marlins signed Koyie Hill, a switch-hitter, to a Minor League contract. Hill has some MLB experience while with the Cubs. He started and had two at-bats on Wednesday in the Marlins’ 5-1 win over the Red Sox at Fort Myers. Hill is an option, but not the only one. But on Wednesday night, Olivo accepted his release, and there are indictations he will wind up with the Marlins.