The Nationals acquired Sanmartin from the Giants on Friday in exchange for Robert Cranz, Spencer Nusbaum of The Athletic reports.
Sanmartin was removed from the Giants' 40-man roster earlier this week, and now he's headed to a new organization. The 30-year-old holds a career 5.37 ERA, 18.8 percent strikeout rate and 10.3 percent walk rate over parts of five major-league seasons, but he has induced grounders at a 55.1 percent clip over that span.