• World Baseball Classic tickets
Murphy and Roark will play for the United States, Martin and Perez for Mexico, and Romero will represent the Dominican Republic. Left-hander R.C. Orlan and catcher Nick Rickles (Israel), catcher Jhonatan Solano and infielder Adrian Sanchez (Colombia) also appeared on rosters.
Roark and Martin are a part of the designated pitcher pool (DPP), which works like this: A team can use up to 10 designated pitchers but can't have more than two on its active roster at a time. Those active DPs can be replaced at the beginning of each of the next two rounds, but only by another DP. Once a DP has been replaced, he cannot return to the active roster for a subsequent round. Using Team USA as an example, Danny Duffy and Roark are the active DPs for the first round of pool play, so they can be replaced on the roster before the second round or the championship round, but only by one of the team's other DPs. And if a DP joins for the second round, he can be replaced for the championship round, but only by another DP.
• Rules for 2017 WBC
Murphy, the 2016 runner-up for the National League Most Valuable Player Award, is coming off a career year during which he hit .347/.390/.595 with a .985 OPS and a career-high 25 home runs in his first year in Washington. This is the first World Baseball Classic for Murphy and Roark, who is also coming off a breakout year. Roark's addition softens the blow suffered when Nationals teammate Max Scherzer was forced to withdraw from the tournament with a stress fracture in his right finger.
Perez pitched for Mexico in the 2006, 2009 and 2013 Classics. He is joined by Martin, who spent limited time in the Majors during the past two seasons but is expected to compete for a spot in Washington's bullpen this spring. The team acquired Romero from the Rays on Tuesday.
The World Baseball Classic runs from March 6-22. In the U.S., games will air live exclusively in English on MLB Network and on an authenticated basis via MLBNetwork.com/watch, while ESPN Deportes and WatchESPN will provide the exclusive Spanish-language coverage. MLB.TV Premium subscribers in the U.S. will have access to watch every tournament game live on any of the streaming service's 400-plus supported devices. Internationally, the tournament will be distributed across all forms of television, internet, mobile and radio in territories excluding the U.S., Puerto Rico and Japan. Get tickets for games at Marlins Park, Tokyo Dome, Gocheok Sky Dome in Seoul, Estadio Charros de Jalisco in Mexico, Petco Park, as well as the Championship Round at Dodger Stadium, while complete coverage -- including schedules, video, stats and gear -- is available at WorldBaseballClassic.com.
Jamal Collier covers the Nationals for MLB.com. Follow him on Twitter at @jamalcollier. This story was not subject to the approval of Major League Baseball or its clubs.