"It's just a way to get him more innings," president of baseball operations Michael Hill said.
DeSclafani's season was mixed with stints up in the big leagues and back in the Minors. It resulted in stretches of going from frequent use to seldom use.
"He missed a few opportunities to start and get some innings," Hill said. "We just wanted to give him the workload to give him a full season of innings and continue his pitch development."
Managing the Rafters will be Andy Haines, the Marlins' Triple-A New Orleans manager.
Prospects from the Marlins, Astros, D-backs, Rockies and Twins will be on the Salt River squad.
DeSclafani is one of four Miami Minor League pitchers going to Arizona. Joining him will be lefties Raudel Lazo and Edgar Olmos, who was called up to the big leagues for one day before being optioned back to New Orleans.
Reid Redman, a right-hander, rounds out the pitchers.
Catcher Chad Wallach, the son of Dodgers bench coach Tim Wallach, is on the Salt River roster, as are infielders Austin Nola and Justin Bohn.
Opening Day for the Arizona Fall League is Oct. 7.
Joe Frisaro is a reporter for MLB.com. He writes a blog, called The Fish Pond. Follow him on Twitter