The promotional giveaway is a Mike Lowell bobblehead.
Lowell, an All-Star third baseman in '03, will be among many players from the squad who will be on hand.
The '03 team emerged from 10 games under .500 in May to win the National League Wild Card. In dramatic fashion, those Marlins beat the Giants in the Division Series, the Cubs in the League Championship Series and the Yankees in the World Series.
"When you look at it, they were so unselfish," said Jack McKeon, the manager of the gritty squad. "It was almost a case where once we learned how to win, no one was going to stop us. No complaints. No gripers."
A number of members from the '03 team were at Saturday's game, including McKeon, Carl Pavano, Mike Mordecai and Brian Banks.
Ivan Rodriguez and Lowell are expected to be on hand Sunday.
"We felt like once we beat San Francisco, we had a chance," said Marlins manager Mike Redmond, who was a backup catcher in '03. "When we got to the Cubs series, we felt we had a chance, even when we were down.
"There were all little signs of things. How we won the San Francisco series, on a bang-bang play. It was all pieced together; it was destiny. It was like we were meant to win that series. We took advantage of any mistake anybody made in that series."
McKeon, a special assistant in the organization, on Saturday was back at Marlins Park two months to the day after having double bypass heart surgery.
The 82-year-old said he felt great, and he is doing his regular workouts like before his procedure.
On doctor's orders, McKeon gave up smoking cigars, which he says bothers him most after dinners. But he notes that once he puts it out of his mind, he is fine.
McKeon actually had two stints managing the Marlins, with the last coming on an interim basis in 2011.
He was the second-oldest manager in MLB history, topped only by Connie Mack, who managed until he was 87.
McKeon joked that in six years he would not rule out returning to managing.
"With this new rebuilt engine, you never know?" he said with a laugh.