Though a deal has yet to be completed, the Washington Nationals expect to name Davey Johnson their next manager within days, front-office sources said, a move that would culminate a bizarre saga with one of this generation’s most accomplished managers taking the helm.

Johnson, 68, and the Nationals were still engaged in final negotiations late Friday night, but had agreed in principle. Johnson could take over Monday, when the Nationals begin a three-game series against the Los Angeles Angels.

General Manager Mike Rizzo said before Friday’s game against the White Sox that John McLaren, who took over following Thursday’s sudden resignation of Jim Riggleman, will manage the Nationals for “days, not weeks.”

Rizzo confirmed the Nationals have spoken with Johnson, currently a Nationals senior adviser and the 1997 American League manager of the year. Johnson last managed in 2000, and he has said several times in the past he did not want to manage again. But Johnson’s affinity for Rizzo and his belief in the Nationals’ players convinced him to return to managing.

Johnson “would enjoy this challenge,” Rizzo said before the game. “Otherwise, he wouldn’t talk about it. He’d just say, ‘No.’ ”

Rizzo declined to comment further after the Nationals finished their 9-5 victory in 14 innings over the White Sox.

Johnson was Rizzo’s first choice as soon as Riggleman resigned following Thursday’s 1-0 victory over Seattle, but owner Ted Lerner had the final say.

Friday evening, Rizzo said the Nationals were still in talks with multiple candidates. But Johnson had emerged as their clear choice. The structure of Johnson’s contract had yet to be decided. Whoever replaces McLaren will manage the Nationals for the remainder of 2011 at minimum, and will be considered to remain for the coming seasons.

“Right now we’re focusing on the remainder of 2011, but we’re going to keep all of our options open depending on the person we get,” Rizzo said. “We’ll keep our options open, and we’ll see where we’re at at the end of 2011. Depending on who the actual guy is, yes I could see a scenario where the 2011 guy could be the manager beyond.”

Riggleman’s resignation blindsided Rizzo, but the Nationals feel exceedingly fortunate to have Johnson already under their employ. Johnson has specialized in turning losing teams into winners quickly.

Johnson has taken three teams to the playoffs, including winning the 1986 World Series with the New York Mets. Johnson last managed in 2000, when he led the Dodgers to an 86-76 record. Johnson compiled a 1,148-888 record in 14 seasons.

Rizzo said the Nationals also discussed the vacancy with other candidates, including some on the Nationals’ current coaching staff. McLaren was not considered as a replacement beyond this weekend.

“I’m just coming here tonight and doing the best I can to get us a ‘W’ ,” said McLaren, 59, the bench coach under Riggleman. “If I’m asked to do it tomorrow night, I’ll do it tomorrow. And if I’m asked to do it next week, I’ll do it next week. I’m not worried about tomorrow or the day after. I’m worried about tonight. That’s all I care about.”

The Nationals, meanwhile, had to contend with the shock of losing their manager as they tried to extend one of the best surges in franchise history, an 11-1 stretch that pushed them to a game over .500. Players said the unique circumstances likely won’t affect them. A baseball manager only has so much influence during the course of one game, anyway.

Third baseman Ryan Zimmerman said players were still excited on the plane ride to Chicago, even after the stunning news. “We played another great game,” he said. “We had a great homestand. Obviously, you never like to see anything happen like that. It’s tough. But it’s s a business. Things like this happen all the time. People get fired. People get released. People get sent down.

“Unfortunately in this kind of sport, you deal with this kind of stuff all the time. I would say this is a little bit different than what we usually deal with, but people come and go all the time. When it comes down to it, nobody is going to feel sorry for us when we go out on the field tonight. So it’s up to us.

“I hate to say it’s not a big deal, because we all respect Jim and it’s tough not having him. But we’re going to go out and play just like we’ve been playing for the [few weeks]. We’re going to go out and play.”