FoxSports.com's Ken Rosenthal tweets that the Red Sox have signed Joe Nelson to a minor league deal.

MLB.com's Alden Gonzalez spoke with Nelson, who said that three or four teams were interested, but that Boston was the best fit.

Nelson pitched for Tampa Bay in 2009, posting a 4.02 ERA in 40 1/3 innings. The 35-year-old righty will have to earn a shot at the big club out of spring training, and his walk rate will have to improve over 2009 (27 in those 40 1/3 innings) to stick with Boston.

The battle for the pen' begins.