The winning candidate's immediate job will be to deal with 11 potential restricted free agents, including new deals for budding stars Carey Price, P.K. Subban and Lars Eller, as well as forward Ryan White and defencemen Alexei Emelin and Rafael Diaz.
Decisions must also be made on impending unrestricted free agents Mathieu Darche, Travis Moen, Brad Staubitz and Chris Campoli.
And the new GM will have to decide what to do with some bad contracts, like that of underperforming centre Scott Gomez who has two more years at a cap hit of US$7.3 million per season, or defenceman Tomas Kaberle, who has two years left at $4.25 per season.
Then there is the free agent market to deal with in July.
The job opening was made official Thursday with the firing of GM Pierre Gauthier.
With the storied Canadiens (29-34-14) languishing in last place in the Eastern Conference, team president Geoff Molson took action.
Habs icon Bob Gainey, a former Canadiens captain and GM, is also leaving the organization. Gainey promoted Gauthier to the GM job in 2010 but stayed on as a consultant.
In cleaning house five games before the end of a miserable regular season, Molson said he was heeding the pleas of thousands of fans who have emailed or sent him Twitter messages to try to make Montreal a dominant franchise again. The Habs won a record 24 Stanley Cups up to its last one in 1993.
He has retained Serge Savard, the GM of that team and veteran of the 1960s and 1970s dynasties, to act as his adviser in finding the right person for the job.
''Our fans care deeply about our team and will have nothing other than a winning team,'' Molson said at a nationally televised news conference at the team's suburban training facility Thursday. ''This season did not deliver on those expectations.
He said the fans want the Canadiens to be what they were in their glory days, a team with ''consistency and stability.''
''Traits that are common to all successful organizations have been lacking in recent years,'' he added. "We need to remember that our fans want us to win, period.
''Just qualifying for the playoffs cannot be our goal or our standard. Not for our team, not for this organization. This organization going forward must set its sights on competing for the game's ultimate prize every season. No lesser standard should be accepted. Our fans and our tradition demand nothing less than this.''
Molson said the list of candidates will be kept confidential, but names have been circulating for weeks as speculation grew that Gauthier would go.
They include Patrick Roy, the former star goaltender who is now co-owner, GM and coach of the QMJHL Quebec Remparts. Former Canadiens assistant GM Julien BriseBois, now with Tampa Bay, broadcaster and former NHL coach Pierre McGuire and former Colorado GM Francois Giguere among others mentioned.
Molson waited until the team was mathematically eliminated from playoff contention to make the move. No time frame was set for naming a new GM, but removing Gauthier right away gives them 10 days more than if they waited until the season ends.
Molson wouldn't confirm widely held suspicions that Gauthier had been on a short leash since mid-season, when it became clear a season that started with great promise was going nowhere.
Gauthier's deadline trades were nearly all in exchange for draft picks rather than players. A bonus the new GM will get is seven picks in the first two rounds of the next two drafts.
Back in February, Molson resorted to Twitter to deny rumours that Gauthier had been axed
The 58-year-old Gauthier was unpopular with fans and the media. He got his nickname The Ghost for being distant and uncommunicative, rarely making himself available to the media and even then, saying little about moves he made.
Molson said the new person must be a good communicator.
But Gauthier did good work in 2010-11 in picking up defensive help when star rearguard Andrei Markov missed all but seven games with injuries and he pulled off a coup last summer in signing winger Erik Cole, who was the team's best player this season.
It all went sour before training camp when, after signing Markov to a new three-year deal, the Russian had a setback in his recovery from knee surgery that would keep him out again until the final month of the season.
Defensive help like James Wisniewski and Brent Sopel had already been let go, and the signing of mistake-prone Campoli was no help.
The power play, formerly a strength, was at or near the bottom of the 30-team league all season. That prompted a trade for Kaberle, a point man of diminishing impact who is signed for another two years at US$4.25 per season. The power play improved only slightly.
Then there was a string of moves that may have tarnished the Canadiens reputation as a ''classy'' organization.
Perry Pearn, a respected veteran assistant coach, was abruptly fired just before a game.
Then head coach Jacques Martin was let go on Dec. 17 and replaced on an interim basis by assistant Randy Cunneyworth, the team's first non-French-speaking coach in decades.
That turned into a public relations disaster that forced Molson, clearly sensitive to public opinion, to issue an apology and vow that the club's next head coach would be bilingual.
That left Cunneyworth as a lame duck.
It didn't help that the team did no better under the new coach than it did under Martin.
Then there was the January trade after the second period of a game of winger Michael Cammalleri, a playoff hero two seasons earlier when the team made a surprise run to the conference final. What irked many was that not only was Cammalleri pulled from the game, but he was not told until afterward where he was going.
He ended up in Calgary for veteran Rene Bourque, who has been a bust in Montreal with four goals in 33 games.
The Canadiens also had bad luck with injuries, including a torn biceps that ended captain Brian Gionta's campaign.
One of the first questions Molson got Thursday was whether the new GM would need to speak French and he replied that it was important, but not more than finding the right person for the job.
However, Savard made it clear that the new one would be bilingual.
''That's easy to understand when 80 per cent of your fan base is French and you have to be able to communicate with them,'' he said.
''It doesn't have to be a French person, but it has to be someone who can communicate in French.''
Savard said experience would be a plus and so perhaps was being a former Canadiens player, but mostly he wanted someone with good judgement.
''I'm one who started in the NHL with no experience and I believe I did fairly well,'' said Savard, who won Stanley Cups in 1986 and 1993 and reached a final in 1989 as a GM. ''Bobby Clarke is another.''
While the search is on, Molson will have assistant GM Larry Carriere helping out. Carriere has a long history in management, but he was made an interim assistant coach when Martin was fired. Goaltending coach Pierre Groulx will move behind the bench as an assistant.
Firing Gauthier all but confirms that Cunneyworth will go at the end of the season, as it will be up to the new GM to pick a coach.
''The biggest thing is that I've got a job to do for the next five games and I'll certainly do my best with our group,'' Cunneyworth said.
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