GORDON Strachan looks like the perfect manager for Scotland: his hair is getting whiter and his brow is already lined, so that will save time.

If Peter Pan was in charge of Scotland he'd look like Gandalf within six months. Every new manager exposes himself to a form of contamination when he takes the job and, for Strachan, the debilitating effects began to eat into him at the weekend. Signing the contract as national manager repositions a man: he instantly goes from being among the many mourners of this country's steep footballing decline, to the guy implicated and gradually sharing the blame for it.

Strachan cut a pretty morose figure in the aftermath of that defeat by Wales. Doubtless he will seem outwardly chirpier when we board the flight to Serbia this morning – a planeload of masochists ready for more – but deep down how can he be anything other than sobered by the cards he's been dealt?

Here is a manager as streetwise and fly as a barrel of monkeys, so even he will be puzzled by the innocent faith he had in his squad until Friday night. He looked at his group, didn't see enough physically powerful figures, and decided that instead of trying to soak pressure and counterattack, the way to deny the Welsh would be to pass and move. He thought he had the players capable of that. He won't think that again for a while.

Much has been made of the lamentable opening period on Friday but it was still instructive to sit through it again yesterday, after the watershed and with the curtains drawn. This is exactly how Scotland began their first qualifier under the new manager: Wales kicked off and immediately put together 13 uninterrupted passes. They hit it long and Grant Hanley's wayward header – Scotland's first touch of the night, and first mistake – went straight to Gareth Bale.

Over the next 16 minutes of impressive Welsh play, with barely a single positive Scottish contribution, this happened: Gary Caldwell gave it straight to Aaron Ramsey, Charlie Mulgrew gave it away, James McArthur gave it away, Robert Snodgrass fouled Joe Ledley, a Graham Dorrans clearance was blocked, Alan Hutton gave it away, Snodgrass was booked for another foul, Dorrans fouled Craig Bellamy, Dorrans gave it away, Hanley almost let in Bale and Allan McGregor untidily covered him, McArthur fouled Ledley, Snodgrass lost the ball, Shaun Maloney gave it away, Hutton gave it away, Hanley gave it away, straight to Bale again. And so it went on and on: too many mistakes to count, nothing but errors and fouls. Add the desperately unlucky loss of Steven Fletcher to injury and it is hard to think of a more demoralising period of goalless play.

Scotland aren't normally as bad as that, and their passing did improve through the end of the first half and the start of the second, but a shocking inability to keep the ball has been a defining characteristic of teams at club and national level throughout the last 15 years of steep decline. Strachan can't do anything about that.

The weaknesses are profound. Other than the excellent McGregor, Scotland are unimpressive across the back, still powerless to find a convincing central defensive partnership. Over the last three, failed campaigns they have conceded 28 goals in 21 games and recorded only six clean sheets.

Six of the outfield starters against Wales – Dorrans, McArthur, Maloney, Snodgrass, Chris Burke and Fletcher – are variously described as attacking, positive, promising or full of potential. True, up to point. But between them they have six goals from 70 caps.

None of the big players currently missing – Darren Fletcher (five goals from 61), Scott Brown (two from 30) and James Morrison (two from 26) – alter that chronic shortcoming. Charlie Adam still hasn't scored, at all. In those last 21 competitive games, there have been only 18 Scottish goals.

This is all the big-picture stuff assembled from the evidence of the five and a half years since the last display which was truly memorable, the 3-1 defeat of Ukraine three managers ago: too many goals conceded, not enough scored, an inability to keep possession and a general lack of height, strength and leadership. Players who perform in the lower half of the Barclays Premier League seem not to take their effective club form to Scotland games. These are the truths which continue unaltered while there is the endless promise of jam tomorrow.

There has been none of that from Strachan so far, only a vow to do everything in his power to improve things. With that in mind, there must be an effort to allow him a period of calm during these remaining five World Cup qualifiers. If he wants to experiment with players or formations – Leigh Griffiths, James McFadden, Johnny Russell when fit, Liam Bridcutt, three at the back, whatever – then let him do it. Scotland is never patient enough to genuinely "write off a campaign" as is sometimes suggested, but surely there is some leeway with a new manager in and this campaign a lost cause.

"It's disrespectful to those who pay their money to watch a match, not a tinkering session," said Strachan himself. "You've got to win games. You can't just say we're going to experiment."

Maybe so, but supporters will happily watch new players or ideas if they either deliver or promise real improvement. The results over their five remaining games, starting in Serbia tomorrow night, will influence Scotland's seeding for the Euro 2016 qualifiers. They are heading for pot 5, their lowest ever. So what? Pot 4, pot 5, at that level it scarcely makes a difference to the prospect of actually qualifying. It's not the seeding that makes it look insurmountable right now, but a squad too limited to make the climb.