The Red Sox needed a catcher because Christian Vazquez will open the season on the disabled list and could miss an extended period of time. Leon could find himself in a platoon situation with Ryan Hanigan.
Leon was out of Minor League options and was not going to be on the Nationals' Major League roster. He was blocked by backup Jose Lobaton.
Leon said he was surprised by the trade, but he is grateful for the people he came in contact with in the Nationals organization.
"[The trade is] going to be good for me," Leon said. "I get another opportunity with another team. [The Nationals] were awesome. They are a really good organization, the coaches. I know all the coaches -- Matt LeCroy, Bob Henley, Randy Knorr. They help me as a player, as a person."
Leon, 26, spent parts of three seasons with the Nationals, hitting .189 in 34 Major League games. In 550 Minor League games over eight seasons, Leon is a career .236 hitter with a .324 on-base percentage.
Bill Ladson is a reporter for MLB.com and writes an MLBlog, All Nats All the Time. He also can be found on Twitter @WashingNats. This story was not subject to the approval of Major League Baseball or its clubs.