The injury replacement hit a three-run homer in Florida's seven-run fifth and the Marlins rallied to beat the New York Mets 9-6.
"You always got to be ready," Maybin said. "Fourth, fifth inning, you got to be ready for anything."
Maine allowed seven runs and seven hits in 4 2/3 innings. He struck out three, walked two, threw two wild pitches and hit consecutive batters in the fourth.
"In this muggy weather it was hard for me to breathe for the first couple innings, but after that it was OK," Maine said.
Sean West (8-6) worked five innings for Florida, yielding three runs, two earned, and seven hits. The rookie left-hander is 5-2 with a 4.67 ERA in his last nine starts.
"That's not the way you want to pick up a win. You want to go six or seven innings," West said.
Jorge Cantu had three hits and scored twice for Florida, which was five games back of wild card-leading Colorado with eight games left entering the day.
"We're hanging around," Marlins manager Fredi Gonzalez said. "That's all we need to do, keep hanging around. Funnier things have happened."
The Mets scored two runs in the ninth against Matt Lindstrom, who helped New York with a one-out throwing error. Lindstrom then struck out David Wright with a runner on second before being replaced by Brendan Donnelly, who fanned Carlos Beltran for his first save.
Fernando Tatis and Beltran homered for New York, which finished with 11 hits.
Wright had a tiebreaking RBI double in the fifth but the Mets missed out on a chance to add to their lead. Wright was a couple of steps from scoring when Jeff Francoeur was out trying to stretch a single into a double, ending the inning.
Wright appeared to let up as he neared home plate.
"That wasn't a good play at all. He came in and apologized to the team, but at the same time you expect more from your core players than what he gave," Mets manager Jerry Manuel said.
Manuel said he spoke to Wright about the play.
"Just a mental mistake. That's my fault," Wright said. "I'll take responsibility and it won't happen again."
Ross left the game after being hit on the left hand while batting with two out in the fourth. Maine also hit the next batter, Brett Carroll, but escaped a bases-loaded jam by striking out West.
"Im not trying to hit anybody," Maine said. "I just had to pitch inside and they got away from me a little bit."
Manuel said SS Jose Reyes (right hamstring) ran "with some intensity" while rehabbing Saturday. "How he feels (Sunday) and the next day will determine the progression," said Manuel, who added Reyes likely will not return in time to play in the season's final series against Houston. ... The first 15,000 fans entering the stadium received Coghlan T-shirts. Most Marlins players wore the white No. 8 shirts during on-field pregame stretching. ... X-rays on Ross were negative and he was day to day. ... Florida 1B Nick Johnson (sick) was unavailable. ... The Marlins had their third straight crowd of 30,000-plus (35,666). The only previous time that happened this season was during a three-game series in June against the New York Yankees.