Barcelona attempt Mission Impossible on Wednesday evening, when Bundesliga champions Bayern Munich visit for a Champions League semi final. The Bavarians have a 4-0 advantage from the first leg and are favourites to set up the first ever all-German final in the history of this competition. Domestic rivals Borussia Dortmund have already booked their place, after beating Real Madrid 4-3 on aggregate.

Lionel Messi (L) and Andres Iniesta
Reuters

Where to Watch Live

Kick-off is set for 7.45pm BST. Live coverage is on Sky Sports 1. Text updates are available on BBC Sport's Web site and on ESPN Soccernet.

Overview

Barcelona come into this game after conceding a late equaliser on the weekend, in a La Liga game against Athletic Bilbao. The domestic championship has been all but sewn up by the Catalans, who boast an 11 point lead over arch-rivals Madrid with only five games to play. But it would have made for a nice boost in morale had they beaten Bilbao before facing Bayern.

The harsh truth is that Barcelona are in deep trouble. They trail the Bavaria club 0-4 after a first leg mauling and need the granddaddy of all comebacks to travel to Wembley for the final. Fans will point to the remarkable turnaround in the first knock-out round, against AC Milan but there are two very important differences here.

The first is Tito Vilanova's men only lost 0-2 at the San Siro; they needed only three goals to go through against the Italian club. In this case, they need five, without reply.

The second difference is that on 12 March, when Barcelona hammered Milan 4-0 at the Nou Camp, a certain Lionel Messi was in particularly inspired form. Unfortunately for fans, the little Argentine has been far from his best in recent games. The 25-year-old was clearly below-par at the Allianz Arena and although he had a brilliant second-half cameo against Bilbao, he will need to produce 90 minutes (and possibly 120 minutes) of sustained genius to knock Jupp Heynckes' side out of the Champions League.

Lionel Messi and Mario Gomez
Reuters

Meanwhile, Bayern travel to Spain in high spirits. The Germans beat SC Freiburg 1-0 on Saturday, despite resting some first team regulars. Heynckes has created an almost irrepressible force in Bayern Munich this season, a feat best illustrated by their record-breaking German championship win. Bayern are 20 points clear of Dortmund in second, with only three games left in the season. Indeed, were Bayern playing in Spain, on this form, they would be winning that championship as well, with or without Barcelona and Madrid.

But that is speculation. The fact is Bayern Munich are heavy favourites to make this their third Champions League final in the last four years. The four-time winners of this competition were beaten by Inter in 2009 and then by Chelsea in 2012 and will be eager to make amends and win a first crown since 2000.

And based on domestic and continental form, it will take Barcelona every bit of talent they have to even get on equal terms with Bayern Munich, never mind defeat them. Bayern are in phenomenal goal scoring form, with 21 goals scored in the last five games. More worryingly for Barcelona, they've only conceded three goals in all that time.

Bayern have not lost a game since Arsenal beat them 0-2, in Germany, in the second leg of the first knock-out round. Even then though, the fact they beat the Gunners 3-1 in the first leg was sufficient to qualify for the quarter final. Vilanova will also have noticed that since the defeat to Arsene Wenger's men, Bayern have only conceded twice in a match once: against SV Hamburg... but they scored nine in reply. We need hardly add the Germans have never conceded more than two goals in a game this season.

There is one wonderful omen for Barcelona fans though. The last time time Bayern Munich played at the Nou Camp, they lost 0-4. That was in 2009 and in the first leg of a quarter final tie the Catalans would win 5-1 on aggregate.

Team Form

Barcelona

    • Last Five (all competitions, most recent first): D L W W D
    • Last Match: Athletic Bilbao 2 - 2 Barcelona
Mario Gomez (R) and Mario Mandzukic
Reuters

Bayern Munich

    • Last Five (all competitions, most recent first): W W W W W
    • Last Match: Bayern Munich 1 - 0 SC Freiburg

Team News

Utility defender Adriano has returned from suspension and is available but Vilanova will be more concerned about the fitness of Argentine Javier Mascherano. The former Liverpool defensive midfielder has been converted into a central defender in recent seasons and his presence will be sorely needed on Wednesday, Unfortunately, he is still recovering from a knee problem and his participation is a doubt. Club captain Carlos Puyol (knee) is still unavailable and will be a big miss, as will Spain left-back Jordi Alba, who is suspended.

Iniesta and Messi both started the weekend game from the bench but will be back in the starting line-up for this match. Sergi Busquets, Xavi and Iniesta will be the likely midfield trio, with Pedro, Messi and David Villa likely to start up front. All eyes, though, will be on defence. Spain centre-back Gerard Pique had a poor game in the first leg and the absence of Puyol, or quality cover for the 35-year-old has really hurt Barcelona this season. And in the absence of both options, Frenchman Eric Abidal may be shifted to that position and could be another weak link.

Probable Line-Up: Valdes; Dani Alves, Pique, Abidal, Montoya; Xavi, Busquets, Iniesta; Pedro, Messi, Villa

Midfielder Toni Kross (thigh) is a doubt but striker Mario Mandzukic returns for this game. Bayern have several players on a yellow card tight rope, including captain Philip Lahm and midfielders Bastian Schweinsteiger and Javi Martinez. However, all those players - certainly these three - will start for a club who have repeatedly stressed the need to be wary of playing Barcelona at home.

Probable Line-Up: Neuer; Lahm, Boateng, Dante, Alaba; Martínez, Schweinsteiger; Robben, Muller, Ribery; Mandzukic