"We are very excited about having Jose," Boras confirmed to MLB.com on Wednesday night. "He has the potential to be a future ace."
Shortly after the 2012 season, Boras said, he met with Fernandez, and the two sides agreed to come together.
The Marlins' first-round pick in 2011, Fernandez is ranked first on the Marlins and seventh overall on the MLB.com's Top 100 Prospects list.
Fernandez is in his first big league Spring Training camp, and on Thursday morning he will start in a B Game against the Cardinals on a back field at the Roger Dean Stadium complex.
Miami intends to have Fernandez open the season at Double-A Jacksonville. If he shows he is ready, he could make the leap to the Majors in 2013.
At Class A Greensboro and advanced Class A Jupiter last year, Fernandez combined for a 14-1 record with a 1.75 ERA. He struck out 158 in 134 innings.
After two straight last-place finishes, the Marlins overhauled their roster, trading away high-priced veterans Jose Reyes, Mark Buehrle and Josh Johnson. The team is being built around a young nucleus, and Fernandez is expected to be a centerpiece.
In 2013, Miami's payroll has dramatically reduced from a year ago, being trimmed from about $100 million to roughly $40 million.
Boras, who represents some of the top-paid players in the game, has not had too many clients play for the Marlins since Jeffrey Loria assumed ownership in 2002.
The biggest name, of course, is Ivan Rodriguez.
In 2003, then a free-agent catcher, Rodriguez signed a one-year, $10 million deal. He became a central figure in the Marlins winning the World Series.
With Fernandez being represented by Boras, it will be interesting to see whether the Marlins reassess their policy on not awarding no-trade clauses.
On Monday night, Loria, was non-committal when asked whether the team would consider changing its policy.