Updated at 4:42 p.m.
Seeking some insurance both in their catching and bullpen ranks, the Nationals have signed veterans Chris Snyder and Jeremy Accardo to minor-league contracts.
Both players received invitations to big-league camp, which opens next week, but both face long odds to come north with the club at the end of spring training.
Snyder, who turns 32 on Feb. 12, could get some significant playing time early this spring while the Nationals ease Wilson Ramos back from surgery to repair a torn ACL. His deal includes an "out" clause that allows him to become a free agent if he doesn't make the big-league roster.
That said, the Nationals do expect Ramos (who suffered his injury in May) to be fully healed and ready to go for the start of the season. They also have veteran Kurt Suzuki (acquired in August) penciled in as their No. 1 catcher for Opening Day, giving Ramos even more time to work his way back into an everyday role.
Snyder does provide more big-league experience than either of the Nationals' other backup plans behind the plate: Jhonatan Solano and Sandy Leon. With 2,435 career plate appearances in the majors with the Diamondbacks, Pirates and Astros, he owns a .225 batting average, .329 on-base percentage and 77 home runs.
A regular in Arizona's lineup from 2007-09, Snyder has dealt with injuries in recent seasons. He had back surgery to repair a herniated disk in 2010 and appeared in only 76 games for Houston last season, hitting just .176.
The Astros held a $4 million option to retain Snyder but elected to take a $500,000 buyout instead after the season, making him a free agent.
Nationals general manager Mike Rizzo, formerly the Diamondbacks' scouting director, originally selected Snyder in the second round of the 2002 draft out of the University of Houston.
Accardo, meanwhile, joins the Nationals after spending parts of the last eight seasons with the Giants, Blue Jays, Orioles, Indians and Athletics. The 31-year-old owns a career 4.30 ERA in 262 appearances, all of them out of the bullpen, and owns 38 career saves (30 of them coming for Toronto in 2007).
The Nationals already are stacked with right-handed relievers, so the odds of Accardo cracking the Opening Day roster appear slim. But he'll provide insurance in case someone ahead of him on the depth chart -- Rafael Soriano, Drew Storen, Tyler Clippard, Ryan Mattheus, Craig Stammen, Henry Rodriguez -- suffers a spring-training injury. He could open the year at Class AAA Syracuse.