The Nationals promoted Adam Cromie to assistant general manager and added two new analysts.
Minniti served as a Nationals assistant general manager for five years and takes on the same title in Arizona.
The event will return to the Walter E. Washington Convention Center.
Span has never won the award and has been nominated twice, while LaRoche claimed the trophy in 2012.
In the return of our question-and-answer, we'll answer the best questions about the Nationals.
After Steve Balboni scouted the Nationals for the Giants, he viewed them as the most complete team in the playoffs.
Former National Josh Willingham is in the World Series for the first time in an 11-year career.
The teams have the main framework for funding for a $135-million two-team facility but don't yet have a site in the county.
The Nationals manager was awarded the honor by his peers. The official manager of the year award is announced Nov. 11.
MLB and the Nationals filed petitions late Monday night in support of the MLB panel's June TV rights ruling.