David Schoenfield: Are Boras clients worth the money?

When Oakland A’s pitcher Barry Zito hit the free-agent market following the 2006 season, his agent, Scott Boras, proclaimed Zito, then 28, would become baseball’s best left-handed starter since Steve Carlton.

He even produced a glossy, 74-page portfolio to show this possibility.

“He will be baseball’s next great ace,” Boras told USA Today. “Barry could be one of the best left-handed pitchers of all time. Players like this are Maddux-esque.”

The San Francisco Giants apparently agreed. They signed Zito to a $126 million contract.

In 2007, Zito went 11-13 with a 4.53 ERA.

In 2008, Zito went 10-17 with a 5.15 ERA.

Maybe Boras meant Mike Maddux, not Greg Maddux.

As always, Boras is a major player in the free-agent market. He represents Mark Teixeira and Manny Ramirez, along with Derek Lowe, Oliver Perez and Jason Varitek, among others.

Zito’s contract has certainly proved disastrous for the Giants, but it’s just one Boras megadeal. Do teams get their money’s worth with Boras clients? We checked other big Boras signings and rated them on our Scott Boras scale: Five Boras heads mean the teams got a great deal; one Boras head means they got fleeced.