Bayern Munich have placed one foot in the Champions League final by dismantling Barcelona 4-0 in the semi-final first leg at the Allianz Arena tonight.

The German giants scored three times in the second half in a relentless performance which sees them firm favourites to progress to the decider to be held at London's Wembley Stadium on May 25.

Thomas Muller opened the scoring in the 25th minute when he headed past Victor Valdes from Dante's knock-down before Mario Gomez doubled the lead four minutes into the second half.

There was a hint of offside as Muller's glancing header from a corner found its way deep into the box before Gomez volleyed home from close range.

In the 73rd minute, it was 3-0 as Arjen Robben dazzled Jordi Alba on the right side of the area before cleverly slotting through the legs of Valdes although Muller could have been pulled up for a body check on Alba as he looked to defend.

Nonetheless, the goal stood and Bayern then took complete control when adding a fourth in the 82nd minute through Muller who flicked in David Alaba's cut back from the left.

Jupp Heynckes' side cut Barcelona to ribbons on occasions in a powerful effort at home and will now need to hold their nerve in defence as Tito Vilanova's Barca will certainly be looking to produce an all-out attacking performance at the Camp Nou in the return bout on May 1.

2012/13 UEFA Champions League semi-final - first leg

Bayern Munich (GER): 4 (Thomas Muller 25'/82', Mario Gomez 49', Arjen Robben 73') Barcelona (SPN): 0

Allianz Arena, Munich - 68,000