Ibanez and Cairo played for Riggleman last year, when all three were with the Mariners. Riggleman took over as interim manager of Seattle on June 19 and guided the club to a 36-54 record.
According to Cairo, Riggleman changed the culture of the club in a positive way, as the team started playing fundamental baseball.
"He is a good person and manager. He let you play baseball. All he asked was for you to play hard," Cairo said. "When you [went] out there, he wanted you to play the game the right way. He emphasized defense, running the bases and being smart -- doing the little things that makes you win games. The players started believing in him."
Ibanez said that Riggleman was put in a tough situation in Seattle and should have been given a full season to prove himself, but the club dismissed Riggleman after the season.
"Riggleman inherited a very difficult situation," Ibanez said. "The only way to improve that situation was to wait for the season to be over. He did the best that he could. In the opinion of the players, Riggleman did a nice job. He was a players' manager. He was very well prepared. "
The Nationals are 21-31 under Riggleman.
Bill Ladson is a reporter for MLB.com. This story was not subject to the approval of Major League Baseball or its clubs.