A reported budget of between £5 and £10 million is being put behind new advertising for the product, which is set to break in early summer.
The win, which followed a final pitch against J. Walter Thompson, complements the Foster's lager business, which the agency has handled for Scottish Courage for the past five years. Media planning and buying remains with MediaVest.
The marathon contest for the account began a year ago when Scottish Courage, which markets, distributes and brews Beck's under licence, split with Mountain View.
D'Arcy was tipped to pick up the business last summer but the appointment is believed to have been blocked by Brauerie, Beck's German parent, which had not been involved at the briefing stage of the pitch.
Brauerie exerts considerable influence over the brand's promotion and is believed to have been behind the decision to pull out the sponsorship of Channel 4 drama halfway through the screening of the gay series Queer as Folk. The decision led to some gay activists calling for a boycott of the brand.
Nick Hurrell, M&C Saatchi's joint chief executive, said the advertising would not attempt to reposition the brand but get consumers to reappraise it.
"Beck's has always had a remarkably strong brand image," he added. "What it has never had is good advertising. We think our work will challenge some of the beer advertising norms."
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