Upsets are required this week if the four away teams in UEFA Champions League action on Tuesday and Wednesday still hope to grace the quarter-finals, each of them having come out second best in their round of 16 openers.
AC Milan travel to face Atletico Madrid knowing they must score at least twice on Spanish soil, while Arsenal and Manchester City face the even stiffer challenge of posting three-goal wins, with the Gunners facing holders Bayern Munich and City visiting Barcelona.
The hardest task of all belongs to Bayer Leverkusen, however, as they must recover from a humbling 4-0 home loss to Paris Saint-Germain. The Bundesliga club need something akin to a miracle in France, even if three teams down the years have bounced back from four-goal first-leg defeats to progress in Europe.
Match of the day
Atletico Madrid-AC Milan (1-0), Estadio Vicente Calderon, Madrid, Tuesday 20.45
"The wind may change directions, but class is permanent - Kaka, Giampaolo Pazzini or Mario Balotelli will score sooner or later," said Clarence Seedorf after his side's 1-0 reverse at the hands of Udinese on Saturday. Low on confidence, I Rossoneri now lie 37 points behind Serie A leaders Juventus, and their fragile self-belief was perfectly summed up by the pair of shots that hit the woodwork during their first-leg defeat by Atletico.
In contrast, the Spanish hopefuls radiate coach Diego Simeone's fierce desire to win, and they got back on track in the Liga with a 2-0 success against Celta Vigo at the weekend, the irrepressible David Villa registering twice. Ominously for Milan, they have lost their last four Champions League knockout ties against Spanish teams, Deportivo La Coruna doing the damage in 2004 before Barcelona prevailed in 2006, 2012 and 2013.
The other games
Tuesday 11 March
Bayern Munich-Arsenal (2-0)
The Bayern juggernaut continues to roll on following a 6-1 victory at Wolfsburg on Saturday, Franck Ribery and Co racking up five goals in the space of 17 minutes to post their 16th consecutive Bundesliga win. They lead the way by an incredible 20 points on the domestic front but are unlikely to take anything for granted against Arsenal after flirting with disaster last season. The European champions won 3-1 in north London at the same stage in 2012/13 before losing 2-0 at home, a result the Bavarians have no intention of repeating as they go from strength to strength under Pep Guardiola.
As for Arsenal, they have slipped behind Chelsea in the Premier League title reckoning but moved a step closer to ending their trophy drought with a 4-1 victory against FA Cup quarter-final rivals Everton. The Gunners have not renounced their Champions League hopes either, and a stirring comeback would be the perfect way to mark manager Arsene Wenger's 175th European game.
Wednesday 12 March
Paris Saint-Germain-Bayer Leverkusen (4-0)
Still struggling for form, Leverkusen had to content themselves with a 1-1 draw at Hannover on Saturday as they warmed up for their daunting trip to the Parc des Princes, where they will have to cope without suspended centre-back Emir Spahic. PSG remain unbeaten at home in 27 European outings, meanwhile, and continue to dominate their domestic scene. Laurent Blanc's side have also scored at least one goal in their last 15 Champions League games.
Barcelona-Manchester City (2-0)
History suggests that a team which wins 2-0 away in the first leg of a Champions League tie has a 98 per cent chance of progressing, but nothing looks cut-and-dried for Barcelona these days. Gerardo Martino's men have been inconsistent since the turn of the year, suffering a trio of defeats including Saturday's 1-0 loss at struggling Real Valladolid.
"As time went on, we were overcome by impotence," explained the man in the dugout, Neymar having displayed none of his typical Brazil brilliance and Lionel Messi experiencing a rare off day in front of goal. More significantly, the Catalan giants proved incapable of imposing their trademark passing game, which will fill Wednesday's visitors with hope. City manager Manuel Pellegrini will nonetheless be banished to the stands as he serves a suspension, and his players will be fully aware that Barça remain a different proposition at the Camp Nou.
Player to watch
Brazilian schemer Kaka was Milan's most influential player in the first leg against Atletico and he will travel full of belief for the decider in the Spanish capital. The 31-year-old contested four games at the Vicente Calderon during his time with Real Madrid and triumphed on each occasion. "Losing the first leg left us with a bitter taste in our mouths, because we gave a very good performance in the first half and just lacked a bit of luck, hitting the crossbar twice," he said. "We have what it takes to wipe out the deficit."
Xavi Hernandez is set to dispute his 161st European match for Barcelona, moving him joint second along with Clarence Seedorf (AC Milan) on the list of continental appearances by a single player for one club. Should he face City, the Spanish international would take himself just seven games shy of record holder and Rossoneri legend Paolo Maldini.
What they said
"It's never over in football. We will go there with belief that we can do it, and with lots of confidence," Arsenal midfielder Alex Oxlade-Chamberlain.
Have your say
Can Manchester City turn things around and spring a surprise against Barcelona?