MIAMI | The Washington Nationals don't know yet where Cristian Guzman will play in the field in 2010. But they may want him to move to second base for the first time in his career, and that's why general manager Mike Rizzo and interim manager Jim Riggleman met with the veteran shortstop Thursday to raise the possibility. Having determined they need another middle infielder next season, and having determined it may make more sense to acquire a shortstop than a second baseman, the Nat...