Celtic are living the dream at last - while Manchester United left Parkhead contemplating a recurring nightmare.

Shunsuke Nakamura's masterful late free-kick and Artur Boruc's last-minute penalty save from Louis Saha were the bare facts of a barely-deserved Celtic win.

It put Gordon Strachan's side into the knockout stage of the Champions League for the first time after a victory that seemed light years away at half-time.

But Strachan's old adversary Sir Alex Ferguson now contemplates the anxious need for a point against the Benfica side that put them out at the same stage of the Champions League last season.

Celtic's win was a triumph for persistence, resilience, bravery and admittedly good fortune.

And it was a triumph for supporters who are as inspirational as any in world football.

In fact, in the first 45 minutes they propped up Celtic as they wobbled in the face of United's onslaught.

For United, it was a defeat that poses serious questions about their ability to challenge again for Europe's elite trophy.

Ferguson's side produced a Rolls Royce first-half performance, but for all the passing and domination, they barely to created a serious chance.

Pretty patterns count for nothing without goals, and while United might scratch their heads wondering how they lost, it was their own lack of cutting edge that caused their downfall.

It left the door open for a Celtic side that had been reeling - and it was an invitation they accepted gratefully in a tumultuous finale.

Ferguson sees his second Champions League win as a glaring omission on his CV, but the signs are that United will fall short again.

The Scot's puzzling decision to field a weakened side against a poor Copenhagen side was the catalyst for an unlikely defeat in Denmark.

It should have been the win that wiped out the worries that now hang over them after this loss.

And the statistics illustrate that United lose too many games on foreign soil to suggest they will prosper at the sharp end of the Champions League.

United should still progress, with only a point required against Benfica, but they have slipped before and this anxiety would have been avoided had complacency not taken over in Copenhagen.

If they fail to progress, United and Ferguson will have only themselves to blame.

And even if they do, I do not see United winning the Champions League this season, despite some of the slick passing football offered up at a vibrant Parkhead.

If they lose games to inferior opposition after exerting almost total domination, how will they beat the more dangerous opponents they may face in the knockout phase?

United may curse their luck and laugh in disbelief at Celtic's win, but the bottom line is they lost... and they have done that far too often away from Old Trafford in the Champions League in recent years.

Celtic will not win the Champions League either, but their major victory is finally reaching the knockout stage.

Credit to Strachan for two shrewd substitutions at the interval, introducing Jiri Jarosik and Shaun Maloney for Evander Sno and Maciej Zurawski.

They did not exactly change the course of the game, but at least they gave Celtic a foundation from which to build the win.

No-one can begrudge Celtic's fans the wild scenes of celebration around Parkhead at the final whistle. The victory was as much theirs as their teams.

No-one can deny their right to party late into the night after making such a contribution to an historic win.

As for United, the old question marks still remain, despite an impressive performance, goals apart.

Can they finally break through the top teams and once again claim the Champions League?

The evidence of the group stages suggests they will be disappointed again.