Morale has to be conserved even it calls for desperate measures. There is an insistence at Manchester United that all had gone splendidly for the opening 10 minutes when they played Barcelona in the 2009 Champions League final. Players and management must be excused if they snatch at whatever low-hanging piece of hope is within reach on the approach to the rematch with Pep Guardiola's side at Wembley. Should United win, it will rank high in the greatest feats of Sir Alex Ferguson.

Some aspects of the meeting two years ago seem to be slipping from the mind. Barcelona were then at a disadvantage, living in the aftermath of a gruelling semi‑final where they were on the brink of defeat until Andrés Iniesta's drive in stoppage time at Stamford Bridge. The scars from that tie were recorded on the disciplinary sheet. Both full-backs, Daniel Alves and Eric Abidal, were suspended for the encounter with United in Rome and Guardiola also lacked the injured centre-half Rafael Márquez.

It was Barcelona's triumph that they controlled the meeting with United to such an extent that their defence did not receive a stringent inspection. The inclusion of Sylvinho, a 35-year-old left-back making his last appearance for the club, went almost unnoticed. Regardless of the stars, Barcelona never forget they are an ensemble. When the ball unaccountably goes missing, they become as well integrated in pressing the opposition as they are when menacing them while in possession.

This year's final need not be a remake. Ferguson's line-up is slightly different now, even if the adjustments are not exactly as he would have wished. With Cristiano Ronaldo gone to Real Madrid, the star quality traditionally associated with the club has been reduced, but there has been an intriguing shift towards well‑integrated team play that continues to be marked despite the large squad at Ferguson's disposal.

United's run to the final has been all but effortless, even when the side could so easily have got caught up in the sort of convoluted and acrimonious tie that can occur when opponents know each other all too well. The quarter-final was tidy, with Chelsea defeated home and away. If there is more efficiency than glamour, Ferguson's side has still maintained its reputation in the Champions League.

Perhaps, too, people overlook outstanding individuals simply because destruction is their main purpose. Any team might crave Rio Ferdinand and Nemanja Vidic as a centre-back combination. Were he not a 40-year-old on the brink of retirement, Edwin van der Sar would be coveted just as much. For all that, Ferguson would be relieved if one more conservative character could be fielded without qualms.

Illness may have brought Darren Fletcher the greatest prominence he has known at United. Suddenly, his presence is craved since no one else in the ranks is so well-adapted to the role of defensive midfielder. If feasible, it would be far better to limit the supply of passes to Messi than hope to stop him once he is on the ball. United face a dilemma familiar to anyone pitted against Barcelona. It seems essential to check them, but teams can become exhausted in the process so that they are incapable of posing a threat.

There is, at least, a reservoir of knowledge at Old Trafford. Ferguson prizes the restraint and tactical awareness of Park Ji-sung. The South Korean has been selected far more regularly in the Champions League this season than he has in the Premier League. Park could not make the bench for the 2008 final against Chelsea, and while he has been tenacious in demonstrating his worth since then it is also the case that Ferguson now depends on such discipline.

Odd as it sounds, United, who are now England's record-holders with 19 League titles, are somewhat underrated. By contrast, Barcelona really have more to do before they are classed with, say, the Ajax "Total Football" side of the early 1970s. They could not surmount the cynicism and managerial acumen of José Mourinho last year and fell to Internazionale in the semi-finals. The Portuguese, though, did not get close to repeating the feat with Real Madrid this season, losing at the Bernabéu and held to a draw at Camp Nou.

Barcelona, with so much practice, may well be more efficient now. United have been highly methodical for years in this tournament, but it may take more than that to topple these opponents.