There comes a point in every manager's tenure when he has no more time for rebuilding, renewing or restarting. This is the point when judgements are no longer provisional, and every match is counted. There is no credit left except what he can earn.
This is where Craig Levein is. After nearly three years as Scotland manager, he begins his second qualification campaign today against Serbia at Hampden Park.
It will not be easy -- Group A also includes Belgium and Croatia. But there is a sense that Levein has to start justifying himself now and that he can only do so with success.
Scotland's manager will stand or fall in the next 10 games by his own tactics, the players he chooses and those he discards.
Levein, admitting yesterday that he has grown into the role, knows that he now needs to deliver. "You don't get an apprenticeship in this game," he said.
"You get thrown in and you have to deal with it. I've learnt an awful lot in the last two years. There's a whole raft of things that I've changed that I didn't do at the start, but it's only because you learn as you go along.
"Nobody wants the best for Scotland more than me. I don't need people to like me. I need people to understand that I am doing everything possible to get Scotland to the World Cup."
Taking Scotland to Brazil, to their first major finals in 16 years, will be very difficult. Scotland are facing two teams with more recent tournament experience in Croatia and Serbia, one with much more talent in Belgium, and two in Macedonia and Wales who can make it difficult on their own turf.
Winning Group A might be beyond Scotland but even to come second they will need a set of impressive results. It will require a serious improvement.
But there was an insistence from the camp yesterday that they are a different team than they were for the last campaign, that Levein's methods are starting to seep into the players, that they are better-equipped for this campaign than they were for the last.
Levein insisted yesterday that his team was "miles better" than the one from two years ago.
"This Scotland team has improved enormously since the start of the last campaign," he said, "and it's our best chance in a long time to qualify."
Gary Caldwell will captain Scotland on the occasion of his 50th cap this afternoon.
The Wigan centre-back, who may be asked to step into midfield, echoed Levein's line that this is a different Scotland team.
"The personnel probably hasn't changed a great deal but the manager knows the group a lot better than he did in the last campaign, he knows what tactics suit us," Caldwell said.
"So we are far better prepared to go into the qualifying campaign than the last time."
Scottish supporters are not quite so impressed with Levein's tactical approach. In one of the crucial early qualifiers for Euro 2012, away in Prague, Levein decided against playing a centre-forward.
To some this was futuristic football, years before Spain's radical triumph.
To others, though, it was negative, fearful football, giving the Czech Republic too much respect, betraying a lack of confidence in their own ability to score a goal.
Worst of all it did not work: Roman Hubnik headed in a second-half corner and Scotland lost 1-0.
There were 6,000 Scottish fans in Prague and by offering them so little Levein lost much of the credit every new manager starts with.
Back at Hampden Park, Scotland went for the win but only managed a 2-2 draw after Michal Kadlec's late penalty. Having taken just one point from Czech Republic, Scotland finished two points behind them in third.
The Czechs advanced to the play-offs, were drawn against Montenegro and went to the finals in Poland and Ukraine.
The frustration, watching a fairly pedestrian Czech side at Euro 2012 was that they were not much better than Scotland. More nerve, drive or skill in either or both of those games could have propelled Levein's team to their first tournament since 1998. The 0-0 draw in Lithuania did not help either.
Levein continues to promote the merits of his defensiveness, but Caldwell yesterday admitted his frustrations at the last failed cycle.
"We have been part of the campaigns that have failed but that only drives you on to want it even more," Caldwell said.
"So we have to use the pain of the last campaign and take it into this one and make sure it doesn't happen again."
Those searching for a guaranteed improvement on the pitch might have hoped for an international return for Steven Fletcher.
The new Sunderland signing, comfortably the best Scottish striker of his generation, remains in international isolation after falling out with Levein.
The fact that Fletcher remains on the outside either shows Levein's strength of character or stubbornness, depending on who you ask. But if Scotland fail to score enough goals to qualify, this issue will return.
Like many others in the Scottish game, Levein's plans have been disrupted by Rangers' relegation into Division 3.
Lee Wallace and Ian Black, Rangers' better Scottish players, are not in Levein's squad.
The decision not to choose those playing at such a basic level has some merit but they may well be among the better players available to him.
With no Fletcher, Levein has a choice between the veteran Kenny Miller and the rather more exciting Jordan Rhodes up front.
Fans hoping to see both play together will be disappointed, as Levein is likely to play 4-5-1. With no James McArthur, Darren Fletcher or Scott Brown, Caldwell may step up into midfield.
With a shortage of full-backs, Paul Dixon may make his debut. Aston Villa outcast Alan Hutton should also play. But this thrown-together team will need to be good.
"What's important to me is the players understand the system -- that the players feel comfortable in the system and they go on the pitch knowing exactly their task, because we have been doing the same sort of thing for a couple of years and reinforcing things as often as we can."
Given the group, a strong start against Serbia today and Macedonia on Tuesday is vital. Six points is the requirement. As Levein must know, the real judgment on his work starts today. (© Independent News Service)
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