Barcelona's failure to break down Manchester United in midweek makes the blaugrana the underdogs going into the second leg of this glamour UEFA Champions League semi-final tie. However, if you're inclined to believe United are as good as through to the final in Moscow; think again.
I have long felt that a goalless draw is a dangerous score for the side playing host to the return match in a two- legged European contest. I'm not alone in this by the way. Back in his days managing Aberdeen in the 1980s, no less a football figure than Alex Ferguson (there were no thoughts of a knighthood back then) felt it was imperative for the first leg visitors to nick an away goal. When his team drew 0-0 away to Servette in 1985, he even expressed a preference for a 2-1 defeat!
Based on Fergie's tactics at the Camp Nou, he no longer sees it quite that way. United were set up to stop Barcelona, rather than to take the game to them. They did this quite superbly. Aesthetically pleasing it most certainly wasn't but the longer the game went on, the less convincing Barca looked going forward.
Job done, then. Or was it? There are countless recent examples of teams prevailing in Europe after drawing 0-0 at home initially. Arsenal took that route to victory against AC Milan in the round of sixteen. Rangers have made a cottage industry out of winning this way in the UEFA Cup and have reaped dividends to the tune of a place in the last four.
Don't misunderstand me. Manchester United are in an advantageous position. Old Trafford will be buzzing on Tuesday, and United will approach the second leg with confidence that they can reach their third European Cup final. Yet at the back of their minds, the players know that a high-wire act will have to be performed. The United defence could be just one set piece, or one moment of carelessness away from elimination.
Barcelona will have to improve. For all their deft flicks and soft touches, the lack of a killer instinct continues to hamper their progress. Lionel Messi, just back from injury, gave his team an excellent hour in the first leg, and his manager Frank Rijkaard will need another top-level display from his inspirational Argentinian.
Carles Puyol, following a one-match European ban, will come in for the suspended Rafa Marquez, strengthening rather than compromising the Barcelona defence.
I believe Rijkaard must play Thierry Henry from the start this time. He knows what it is to score against Manchester United, having done it nine times in 18 games with Arsenal. Henry has cut a lonely figure in his first season with Barcelona, but his experience will be invaluable at Old Trafford.
Cristiano Ronaldo, whose early penalty miss on Wednesday dented his hopes of breaking Denis Law's single season Manchester United scoring record, has promised he'll make amends by netting against Barca at Old Trafford.
I can't imagine Sir Alex will make wholesale changes, although a case can be made for Anderson's boundless energy. Stomach bug victim Nemanja Vidic will be welcomed back into the defence, allowing Wes Brown to revert to right-back.
If Barca score in Manchester, I can see them going through. However, goals have been rather difficult to come by for the blaugrana recently.
In the other semi-final, concluding on Wednesday night, Chelsea are now rightly favourites to go through after a 1-1 draw against Liverpool in an Anfield first leg of sketchy quality.
The return of Michael Essien from suspension boosts Avram Grant's options, and there's a feeling that the Londoners just have to avoid fundamental mistakes now. Grant, in the light of John Arne Riise's late gift, might finally think his luck is in.
But Liverpool, despite never having scored at Stamford Bridge under Rafa Benitez, can't be counted out. Fernando Torres, so clinical this season had a complete nightmare. It's difficult to envisage a repeat performance in the return.
That Liverpool now have to go for it (a goalless draw won't do), will serve only to help the spectacle. Extra time might be a reasonable bet and should the tie go to penalties, I know who my money's on! Liverpool are the undisputed penalty kings, until proven otherwise.
So, who'll march on to Moscow? We still have a few midweek twists and turns to circumnavigate but I'll stand by my original prediction of Manchester United against Liverpool.