From ESPN:
Across the 43-year history of their rivalry, Barcelona have never knocked Liverpool out of Europe, never defeated the Reds at the Camp Nou. Four home matches: two defeats, two draws, one solitary goal scored -- 12 years ago, by Deco. It's an angry blemish scarring an otherwise superb European record from a club that, like Liverpool, is pursuing its sixth Champions League trophy.
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It's true Barcelona's home record could make the Camp Nou seem like an unassailable citadel. No team in Europe has an equivalent record of 31 home games in UEFA competition without defeat.
Liverpool, as powerful as they are and as much as the two rivals' states at present makes them feel like favourites, face a club that has won 28 and drawn three in the past six years, scoring 91 while conceding just 15 times. Pretty remarkable.