Barcelona's dominant lead at the top of LaLiga and place in the Copa del Rey final means Lionel Messi seems certain to burnish his reputation as one of the all-time greats with yet more silverware this season.
However, on Tuesday at Stamford Bridge, a troubling foe comes into view for the mercurial Argentinian.
Despite facing Chelsea eight times in the Champions League during his stellar career, Messi has never scored against the reigning Premier League champions.
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There is no other opponent he has faced more frequently without finding the net. Here, we look back at how Chelsea have managed to stop the unstoppable force.
2005-06 Champions League round of 16 – Barcelona beat Chelsea 3-2 on aggregate
An 18-year-old Messi was enjoying a breakthrough season in the Barcelona first-team and turned in a dazzling performance in a 2-1 win at Stamford Bridge, twisting and turning Asier del Horno to frustration and a red-card challenge. The injury problems that dogged Messi's early years struck in the return leg, with a hamstring injury ensuring the 1-1 draw at Camp Nou was his last appearance of a campaign in which Frank Rijkaard's side marched to European glory.
2006-07 Champions League group stage – Chelsea 1 Barcelona 0; Barcelona 2 Chelsea 2
Didier Drogba scored the only goal in London as Chelsea gained a measure of revenge for the previous season and it was Frank Lampard, not Messi, who produced a moment of Camp Nou magic in the return game. The England midfielder spun to lob Victor Valdes – Chelsea's first equaliser in a 2-2 draw that Drogba secured deep into stoppage time. Chelsea topped Group A and Barcelona were eliminated in the first knockout round by eventual runners-up Liverpool.
2008-09 Champions League semi-final – Barcelona progress on away goals
Messi was the jewel in Pep Guardiola's all-conquering treble side and would go on to score in the 2-0 final triumph over Manchester United in Rome. He had no such joy in a cagey, controversial semi-final encounter, where the first leg in Catalonia ended goalless. But Messi was on hand to supply the pass for Andres Iniesta to score his stunning and decisive injury-time equaliser in a 1-1 draw at Stamford Bridge.
2011-12 Champions League semi-final – Chelsea beat Barcelona 3-2 on aggregate
Barca's old tormentor Drogba gave the Blues a slender 1-0 advantage after the first leg in London but Chelsea were in trouble at Camp Nou when Sergio Busquets and Iniesta scored either side of John Terry being sent off for lashing out at Alexis Sanchez. But a wonderful chipped finish from Ramires put the visitors ahead on away goals and Messi rattled the crossbar with a penalty as Barcelona became increasingly desperate. When Fernando Torres broke clear to sensationally settle the tie, Messi's heartache was evident.