Marlins manager Ozzie Guillen has indicated that Juan Carlos Oviedo could share the closer job with Health Bell when he returns. Guillen said previously that Bell would retain his role, but it sounds like he's changed his tune as the 34-year-old's struggles have continued. "I will [treat] that as a big trade we make for the [playoff] run," Guillen said. "He's going to help the bullpen. A day like today [when Bell is unavailable], he'll take Bell's spot. [Other times] we'll see how Bell's throwing and we'll flip-flop each for whatever reason. It's going to be a big lift. Hopefully, he'll throw the ball like he has in the past.'' Oviedo will begin a rehab assignment with High-A Jupiter Monday. He's expected to stay with them for two weeks before rejoining the big club on July 23rd.