Josh Johnson was selected by the Marlins in the fourth round of the 2002 draft, and made his first appearance with the club in September of 2005, posting a 3.65 ERA in 12.1 innings of relief work. He did not figure into any decisions.
In 2006, Johnson made the Marlins opening day roster, posting a 1-2 record with a 3.86 ERA. He joined the rotation starting in May, making regular starts and finishing with a 12-7 record and an ERA of 3.10. He finished fourth in the NL Rookie-of-the-Year voting.
2007 saw Johnson spend the whole season on the DL, minus four starts in June and July, finishing 0-3 with an ERA of 7.47 over 15.2 innings.
A lingering ailment kept Johnson on the sideline through the first half of 2008. Making his debut in July, Johnson ended the season with a 7-1 record and a 3.61 ERA, striking out 77 batters in 87.1 innings pitched.
Johnson managed to stay healthy in 2009, enjoying a career high with 33 starts and making his first All-Star team. He posted a 15-5 record with a 3.23 ERA, finishing in the NL top ten in wins, strikeouts, and WHIP.
2010 was Johnson's best season to date, as he led the NL with a 2.30 ERA, again making the All-Star roster and finishing fifth in the end of the year NL Cy Young Award vote. He went 11-6 in 28 games, striking out in excess of one batter per inning pitched.
Johnson again spent a substanial portion of the 2011 season on the DL, this time with a right shoulder inflammation. In nine games he posted a 3-1 record with a devilishly low 1.64 ERA in 60.1 innings and a WHIP of 0.978.
In total, Johnson has posted a 48-23 record and a 2.98 ERA with a 1.220 WHIP. He has struck out 667 batters in 725.1 innings. When healthy, Johnson is heir apparent to the Florida Marlins number one starting slot.