Traded to the Marlins while still in the minors with Arizona, Brad Penny proved himself a hard-throwing right-hander with a commanding mound presence. He quickly went from prospect to reliable starter. Although he later became an All-Star in Los Angeles, his time in Miami was marked by consistent pitching that helped secure the franchise's second championship.

In 2000, Penny became a regular in the rotation, and by 2001, he proved he belonged with a 3.69 ERA and a personal best of 154 strikeouts over 205 innings. During these early seasons, he served as a consistent presence despite roster changes. By 2003, he had established the dependability essential for a deep playoff run, ending the regular season with 14 wins and helping Florida secure a Wild Card spot.

The best story of Penny’s career in South Florida was the 2003 World Series.  During baseball’s biggest stage, Penny started and won both Game 1 and Game 5. He was a giant of efficiency in those two outings, allowing only five runs over 14 innings (a 3.21 ERA) and outdueling David Wells and José Contreras. While he wasn't named the MVP of the series, his two victories were the foundational pillars that allowed the Marlins to secure their second World Series title in six games.

He was traded to the Dodgers at the 2004 Trade Deadline but returned for a brief stop a decade later, though he did not play much in his second run.  With the Marlins, he had a record of 50-43 with a 4.12 ERA and 583 Strikeouts.

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