Before the Marlins beat the Mets, 5-4, on Thursday, the right-hander threw on flat ground with pitching coach Randy St. Claire at the Roger Dean Stadium complex.
"It went very well. He felt great," St. Claire said. "He played long toss and stretched it way out. It felt really good. He will have a side [session on Friday]."
Initially, the right-hander was set to make his first Grapefruit League start on Friday night against the Nationals at Roger Dean Stadium. Instead, Wade LeBlanc will face off against Washington's Stephen Strasburg.
The hope was to push Sanchez back one day, but that idea has been scrapped. Josh Johnson will start on Saturday, and Mark Buehrle is set for Sunday.
Sanchez will throw off the mound Friday. If that goes well, he will face hitters in live batting practice on Sunday, keeping him on schedule to join the rotation next Wednesday to face the Rays. The Marlins are trusting Sanchez will tell them when he feels ready to pitch in an exhibition game.
"He's going to tell us how to handle it," manager Ozzie Guillen said.
"We're not going to put a guy out there just because. When he's ready to pitch, he will pitch. I don't think it's a big deal, but it could be a big deal if we don't handle it the right way."
Guillen added that Sanchez is competing with Carlos Zambrano to fill either the fourth or fifth spot in the rotation.