Longtime Phillies president and CEO David Montgomery has new duties as he returns from a five-month medical leave of absence. Montgomery now will serve in the position of team chairman while Pat Gillick continues as president, the team said Wednesday.

The front-office shake-up could pave the way for another new team president in the next year or two. Gillick, the architect of the 2008 world championship team, said Wednesday night in a telephone interview that he doesn't see himself in the position two or three years from now but "definitely" at least through this baseball season.

Gillick, 77, held the position on an interim basis since Aug. 28, when Montgomery took a leave while recovering from surgery in May to remove cancer from his jawbone. A December test showed no recurrence of the cancer, Montgomery said Wednesday. He said he is set for another scan in six months.

The positive health report, Montgomery said, set into motion the changes announced Wednesday, offering some clarity regarding the overseer of at least the early stages of the Phillies' rebuilding efforts. Gillick, a 2011 Baseball Hall of Fame inductee, will lead the daily baseball operations for an undetermined period.

"I think that's really up to him," Montgomery said in a telephone interview from his office at Citizens Bank Park. "I'm just pleased that he's willing to give us the opportunity to take advantage of him doing it now, which will help [general manager Ruben Amaro Jr.] and help the whole process of us getting back."

Montgomery assumes the position held last by Bill Giles, whom Montgomery succeeded as Phillies president in June 1997. Montgomery will remain a presence at the ballpark in addition to staying involved with Major League Baseball, acting as chairman of the Philadelphia Sports Congress and on the board of the Greater Philadelphia Chamber of Commerce.

Giles, who as chairman did not influence baseball decisions, assumes the title of chairman emeritus.

"The beauty of this is that as far as direct oversight over Ruben, that's Pat," Montgomery said. "Whatever we did wrong the last few years, blame me and give Ruben and Pat a clean sheet to figure it out from here."

Gillick previously served as general manager for four teams: the Toronto Blue Jays, the Baltimore Orioles, the Seattle Mariners, and the Phillies. He won championships with the Blue Jays in 1992 and '93 before winning with the Phillies.

He stepped down from his GM post after the 2008 World Series victory and transitioned into a role as a senior adviser to his successor, Amaro. Located then in Seattle, Gillick helped the Phillies with free agency and scouted significant prospects on the West Coast ahead of the annual summer draft.

Since taking over as interim president, Gillick has said on several occasions that he doesn't expect the Phillies to contend again until 2017 or 2018. Last month, the team also parted ways with Jimmy Rollins, Marlon Byrd, and Antonio Bastardo as the first steps of its rebuilding process.

"Look, it's a challenging time for Ruben," Montgomery said. "I think it's great that he has somebody with Pat's background to lean on to help him through this. We want to get back as quickly as we can. That's the goal."

Montgomery, who grew up in Roxborough, has been with the Phillies since 1971, when he started as a ticket salesman. After advancing through the ranks of the organization, he was at the helm for parts of 18 baseball seasons, including the team's five consecutive division titles from 2007 to 2011.

Regarding his new role, he said, "It has worked out very well." He expressed pleasure with being back at work and said he's excited to travel to Clearwater, Fla., for spring training.

For the first time in a while, it won't be as team president.

@jakemkaplan