Jim Riggleman says he doesn’t regret resigning as Nationals manager in June 2011. (Ricky Carioti/The Washington Post)

Jim Riggleman has settled into his usual offseason routine, back home in Tampa, tending to the errands that piled up during his summer out on the road. Riggleman watches baseball intently on television, but that is as close as he comes to the Washington Nationals, the powerhouse-in-waiting that he was managing, incredibly, just 15 months ago.

As the 98-win Nationals prepare to begin the first postseason in team history, Riggleman says he harbors no regret about the half-bold, half-crazy, all-bizarre decision he made last June 24, when he resigned as Nationals manager over a contract dispute with General Manager Mike Rizzo.

He does not feel as if he missed the chance to guide the Nationals in their breakout season, expressing doubt he would have been brought back even if he had not walked away because he had no guaranteed years remaining on his contract.

“I don’t know that I would have been a part of this team if I . . . whatever,” Riggleman said in a telephone conversation Thursday afternoon. “For me, I was a part of the ’11 team. I was a part of the ’10 team. That ’12 team is a whole unique situation. I’m going to enjoy watching them in the postseason. I think they’ve got as good a chance as anybody. Mike’s done a great job putting that team together. I think that they’re going to be good for a long time.”

Riggleman sounded more appreciative than bitter about his experience with the Nationals. He absorbed 172 losses and won just 140 games after he took over as interim manager in 2009. And even after his Johnny Paycheck departure, he said he considers his time managing the Nationals a fond experience.

“I look back at it positively,” Riggleman said. “I left on my own terms. As I’ve told people many times, it wasn’t a smart thing to do. It wasn’t something I would advise someone I care about to do. I think I did the right thing. I didn’t do the smart thing, but I did the right thing.

“Managing in the major league is a great experience. It’s all-encompassing. It needs your undivided attention. I just found myself in a position where I wasn’t going to be giving my undivided attention if my mind was on this other stuff. I felt like it wouldn’t be fair for me to keep taking the paycheck, so I walked away from it. It’s a tremendous privilege. I’m indebted to the Lerners and to Mike for giving me the opportunity.”

As Riggleman led last-place teams at the end of 2009 and in 2010, he could see the Nationals’ bright future taking shape. He was managing when the Nationals signed Stephen Strasburg and drafted Bryce Harper. Before he resigned, the Nationals had won 11 out of 12 games.

“I remember having conversations with front office folks,” Riggleman said. “We felt like we had a chance to be pretty good in ’12, building toward ’13. That was before the acquisitions of Gio Gonzalez and Edwin Jackson. The success you’re going to have starts with the starting pitching, and they’ve got the best.”

Riggleman moved on last year as a scout with the San Francisco Giants. He enjoyed this year managing the Pensacola Blue Wahoos, the Class AA affiliate of the Cincinnati Reds. He managed Billy Hamilton, the speedster who set the minor league stolen base record with 155 this year. He liked working with players energized by the goal of making the big leagues, rather than veterans who may be bitter about playing time.

“The thing that I did enjoy, when you’re managing in the big leagues, the juices are really flowing,” Riggleman said. “I didn’t know for sure if it would be the same, because I hadn’t managed [in the minors] in 20 years. When the umpire said, ‘play ball,’ the juices were really flowing. I didn’t feel like I had lost any intensity at all in the minor leagues.”

Riggleman could have been back in the major leagues this season. After the Houston Astros fired Brad Mills on Aug. 19, they made Riggleman an offer: Manage on an interim basis for the remainder of the season, then return in 2013 as a coach.

Riggleman turned it down. Rather the manage in the majors again, he stayed at Pensacola. Really, Houston would have been in the same situation he walked away from with the Nationals: managing without a certain future beyond the end of the season.

“If I was going to be a candidate to manage, I would have done that,” Riggleman said. “I was flattered they wanted me on the staff. The Reds have been great to me. For me to leave my club and then come back to the Reds as a manger, I didn’t want to do that. At this time, coaching in the big leagues didn’t appeal to me.”

Riggleman plans to return to the Pensacola next year, far away from the majors and even farther away from the Nationals. He remains a baseball man still, at peace with his decision and content with his job, save maybe one detail.

“The downside is always the same,” Riggleman said. “The bus rides.”