PITTSBURGH -- It may not be the biggest priority this offseason, but the Pirates are keeping a keen eye on the catchers who hit the free-agent market.

On the surface, the Bucs would seem to have little need for an additional catcher. Ryan Doumit is well established at the Major League level, and Jason Jaramillo proved in 2009 that he can certainly be a capable backup. Pittsburgh also touts above-average organizational depth at the catching position, with 2009 first-round Draft pick Tony Sanchez leading that class.

So what is compelling general manager Neal Huntington to continue exploring the catchers available in the Major League and Minor League free-agent market?

Well, to begin with, the Pirates lost a bit of their depth Friday when they designated Robinzon Diaz for assignment to clear space on the 40-man roster for young prospects. Diaz sat third on the catching depth chart in '09, though he did spend much of the season with the big league club because of Doumit's wrist injury.

Diaz cannot be sent outright to the Minors, meaning that if the Pirates don't trade him within the next week, he'll become a Minor League free agent. He is not expected to look to return to the organization.

"[Diaz] was frustrated at times this year as guys passed him by," Huntington said. "And it's our anticipation that he would sign elsewhere."

With Diaz out, Erik Kratz, who has already re-signed with the Pirates, currently falls behind Doumit and Jaramillo in the depth chart. Kratz had a standout season among Triple-A catchers, as he was named both a midseason and postseason All-Star. However, Kratz has never played in the Majors, and there are still concerns about whether or not he'd be ready to if either Doumit or Jaramillo were injured.

"Our expectations are that he'll be the classic emergency third catcher," Huntington said of Kratz. "But we'll look at the Major League and Minor League market to see if there is somebody that complements our club."

As a result, it's certainly possible that the Pirates will sign a veteran catcher to a Minor League deal with the intention of keeping him in Triple-A as an emergency Major League backup.

Now, there is another reason for the Pirates to keep an eye on the catchers available this winter, and that would be in case the club decides to deal Doumit. Pittsburgh has made it clear that none of the organization's players are immune from the possibility of being traded. In fact, a recent report cited a source as saying the Pirates offered Doumit to the Brewers for shortstop J.J. Hardy just weeks ago.

Why consider trading Doumit? Well, the Pirates are content with Jaramillo's defensive abilities behind the plate and don't seem to be hesitant to use him in an everyday role. Pittsburgh is also well aware that a switch-hitting catcher is a valuable trade commodity, even if Doumit is coming off a subpar, injury-plagued season. Doumit's favorable contract, which runs through 2013 if both club options are exercised, would also be appealing to teams needing a starting backstop.

There's no question the Pirates would listen to offers for Doumit, but the club would need to improve upon its duo of Jaramillo and Kratz if the team were actually to trade Doumit away before '10.