It never ceases to amaze Alex Ferguson how every time Manchester United find themselves on the wrong end of a bad result it can be dramatised into the beginnings of a crisis.

In considering their extraordinary disintegration against Deportivo la Coruna at the Estadio Riazor in Galicia on Tuesday it is important, therefore, to keep a sense of perspective.

Ferguson can reflect that his side, deploying an unfamiliar system and confronting La Liga's second-placed team, came within four minutes of posting their finest result since two late goals of their own left Bayern Munich's players prostrate in the 1999 European Cup final.

As United have already beaten Lille and have yet to meet Olympiakos, the weakest team in Group G, it would also be premature to believe the damage to their chances of reaching the second stage of the Champions League might be irreparable.

Yet Ferguson, privately at least, must concede that the feeling of invincibility that once surrounded the Premiership champions has scarcely been evident this far into his final season. It has been a time for experimentation and even though Ferguson evaded any questions about his tactics in the immediate aftermath of Deportivo's late two-goal flourish it is clear that the United manager will have to tinker with his methods once again.

Roy Keane had spoken of the need to "get boring", but Ferguson may consider that the defensive system he tried in Spain, with Keane shielding the back four and Ruud van Nistelrooy alone in attack, went too much against United's attacking instincts.

Mauro Silva, Deportivo's imposing Brazilian, lent support to this view.

"They didn't play like the team we know. They were not the attacking force they have shown in Europe over the last few years," he said. "They invited us to attack by sitting so deep. Van Nistelrooy was on his own and that made it easier for us to descend upon them."

When Ferguson settles on the best formation they will take some stopping but, for the time being, finding the best way to accommodate Keane, Paul Scholes and Juan Sebastian Veron behind Van Nistelrooy eludes him.

Scholes is arguably United's most rounded player, Veron's £29.1m sterling price tag means he can hardly be dropped and Keane is an automatic choice and rightly so. Yet Van Nistelrooy clearly needs more support than he is getting.

"There are one or two bits and pieces we have to improve," Veron admitted before leaving the Riazor, but his pay-off line was worth remembering.

"The whole season is not over," he said. "Let's not forget that."