Jose Fernandez, the 20-year-old rookie, was informed he was trading spots with Ricky Nolasco.
Fernandez got the start for the 2:10 p.m. ET game, while Nolasco will pitch the nightcap, scheduled for 8:10 p.m. ET.
"We weren't really sure what the weather was going to be like today," manager Mike Redmond said. "There was the possibility of just playing one game today, and not knowing if it was going to snow again, or what. When we saw the sunshine, it made sense to put Fernandez up to pitch Game 1. Ricky's a little more accustomed to throwing in the cooler weather."
Snow and sleet led to Monday's game being postponed. Up until Tuesday morning, team officials were weighing all options.
"We really didn't think we'd get two games in," Marlins general manager Michael Hill said.
If the second game couldn't be played, playing on Wednesday, a scheduled off-day for Miami, was discussed.
Joe Frisaro is a reporter for MLB.com. He writes a blog, called The Fish Pond. Follow him on Twitter