Nats sign Durbin; team's farm system rated No. 1

The Nationals added another arm to their bullpen mix today, agreeing to a minor league contract with right-hander Chad Durbin, according to this tweet from ESPN's Jerry Crasnick. No word on whether Durbin will get an invitation to spring training, but it's a good bet he'll be in the major league clubhouse when pitchers and catchers report to Space Coast Stadium on Feb. 19. The 34-year-old Durbin was 2-2 with a 5.53 ERA in 56 games for the Indians last season. In 12 major league seasons with the Royals, Indians, Diamondbacks, Tigers and Phillies, he's 38-46 with a 5.10 ERA in 364 appearances, including 75 starts. His best season came in 2008, when he went 5-4 with a 2.87 ERA and a save for the World Series champion Phillies. In other news, Baseball America's 2012 Prospect Handbook is out and ranks the Nationals' minor league system as No. 1 in baseball - with a caveat. The ranking was determined before the Nationals traded four of their top prospects - catcher Derek Norris, left-hander Tommy Milone, and right-handers Brad Peacock and A.J. Cole - to the A's for lefty Gio Gonzalez. The Nationals ranked 13th last year. "The Nationals have come a long way in our organization rankings in a short time after ranking dead last just five years ago," said Baseball America executive editor Jim Callis in a team-issued press release. "They've been as aggressive as any team in the draft, which is the best way to build a team and a farm system. They've gotten the No. 1 player in our draft rankings for three years in a row with Stephen Strasburg, Bryce Harper and Anthony Rendon, and they've added a lot of quality depth around them." Nationals general manager Mike Rizzo said the bounty reflects the team's desire to build a perennial contender. "Between our draft picks, our trades, and our free agent acquisitions over the last three to five years, I don't think there is a question in anyone's minds about our commitment to building a contender in the Nation's Capital," Rizzo said. "We had a strategy, we stuck to it, and hopefully, we will begin to see dividends in 2012 and well beyond." Update: Baseball America will provide updated rankings in mid-March. Update: Durbin gets a spring training invite in the deal, which the Nationals have made official via email.