The Nationals and Ryan Zimmerman have agreed to a six-year, $100 million contract extension, according to sources. The third baseman also received a full no-trade clause in the deal. Zimmerman will earn an average of $16.7 million over the course of his contract, second only to the $27.5 million Alex Rodriguez earns in New York among third baseman. His current contract was set to expire after the 2013 season and he had set a deadline of this weekend to complete a deal. Zimmerman, who is due to earn $26 million over the next two seasons of his current contract, could potentially earn $150 million if a seventh-year option for 2020 is picked up, the sources said.