Global brand director Jon Potter has issued the advertising agency a revised brief to reignite the brand, whose UK sales have been flat for the past two years.
The agency has struggled to match the triumph of its award-winning "surfer" advertisement of 1999, which has consistently been voted best ever ad in media polls.
Potter admitted that AMV BBDO was "under a bit of pressure", but said he was not talking to other agencies. He added that he wanted to retain the global brand proposition "Believe".
The last Guinness ad by AMV, "lava", showed a man running barefoot through molten lava to rescue a keg of Guinness from a burning building, a feat for which he is hailed a hero.
Before that, its creative for the brand was "dream club", which attracted criticism for being too obscure.
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