For three years, John McLaren has waited for his next opportunity to manage a major league team. Friday, he'll get that chance — but it likely will be a short-lived tenure.

Following the resignation of manager Jim Riggleman on Thursday afternoon, McLaren was expected to be named the team's interim manager. But sources indicate he may only manage through the series against the White Sox in Chicago.

The Nationals' plan at this point, according to a source, is to have a manager for the rest of the season in place by Monday. Senior advisor to the general manager Davey Johnson is high on their list of candidates.

Johnson's track record as a player and manager in the majors is well-documented. He has managed the Cincinnati Reds, Baltimore Orioles, Los Angeles Dodgers and New York Mets, winning the 1986 World Series with New York. He has been a member of the Nationals' front office since November 2009 but hasn't managed a big-league team since Los Angeles in 1999-2000.

With McLaren, the Nationals' bench coach since the start of the 2010 season, at the helm for the next three days, Washington will try to continue the winning brand of baseball that has brought it to third place in the National League East.