WASHINGTON -- Nationals general manager Mike Rizzo said Thursday that the search for a new manager will be in full swing soon but that the skipper may not be named until the postseason is over.

Rizzo has spent most of the offseason revamping the front office. Recently, the Nationals named Roy Clark as vice president of player personnel, Johnny DiPuglia the director of Latin American operations and Doug Harris as the director of player development. The team also promoted Kris Kline to director of scouting.

"The managerial search is going to begin a little bit more seriously in the very near future," Rizzo said. "But I wanted to make sure we got these vital hirings in the front office as the first part of putting our plan in place."

Rizzo said interim manager Jim Riggleman is still a strong candidate to remain the manager. During the second half of the season, the Nationals went 33-42 under Riggleman.

"We are [getting ready] to make phone calls, cutting down a long list into a smaller list and discussing with specific people about the managerial job," Rizzo said. "Like I said in the past, we have a terrific in-house candidate in Jim Riggleman, who has as good a chance as anybody to become the manager for the Washington Nationals. The search is going to begin a little more seriously in the very near future."

Besides Riggleman, Chip Hale, Bob Melvin and Bobby Valentine have been floated as likely candidates to be interviewed. Another person the Nationals may look at is Dave Duncan, currently the pitching coach of the Cardinals. However, there are reports that Duncan most likely will return to St. Louis.

Through his representative, Burton Rocks, Riggleman said he was aware the Nationals were going to take care of the front office before searching for a manager.

"Mike had told Jim of his plan to revamp the front office first," Rocks said. "Jim just wants the process to play out. Obviously, at the end of the day, Jim really enjoyed working for Mike and [team president] Stan Kasten. Jim wants to be a part of the entire Nationals family."