Rosenthal’s Latest: D’Backs, Robertson, Pirates

Some notes from Ken Rosenthal of FoxSports.com…

• The Diamondbacks continue to pursue a number three or four starter in the wake of Brandon Webb's setback. A club official acknowledged that such a pickup was possible, but “I don’t think any team will be willing to give up that kind of pitcher at the start of the season.”
• Rosenthal says the team has infield depth to use in a trade, and reiterated that they'd love to move Chris Snyder and the $11.25MM left on his contract. The Rangers and Red Sox are said to be looking for infielders, and the Mariners could join them following Jack Hannahan's injury.
• The Tigers are shopping Nate Robertson, but Arizona doesn't consider him enough of an upgrade. Zach Duke and Paul Maholm are not available.
• The best available starter may be Chad Gaudin, who was released by the Yankees on Thursday.  
• The Brewers considered a Jeff Suppan for Snyder trade, but didn't want to take on Snyder's 2011 salary. Suppan will earn $12.5MM this season, the final one on his contract.
• The Cubs do not expect to make a trade for a reliever before Opening Day, but they've scouted Jason Frasor and Scott Downs, plus Luke Gregerson of the Padres.
• Nick Green has an out clause in his minor league contract, but the Dodgers may add him to the roster to serve as the backup shortstop.