(CNN) -- The mystery behind the peculiar inscriptions "Out of the Blue" and "True Blue" which first appeared on Sauber engine covers at the Chinese Grand Prix has finally been revealed. The Swiss Formula One team has joined forces with English football club Chelsea in an innovative marketing ploy aimed at attracting a global audience -- and boost sponsorship. It's the first such partnership between the sports, and from next week's Spanish Grand Prix all Sauber cars will be emblazoned with the slogan "Welcome Chelsea FC." Chelsea, owned by Russian billionaire Roman Abramovich, already has an international fanbase but can now also capitalize on the following of Sauber's drivers -- Mexican Sergio Perez and Kamui Kobayashi of Japan.
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Sauber F1 cars bear Chelsea FC "teasers" at China and Bahrain grands prix
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The sports organizations join forces in a ground-breaking marketing partnership
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They hope to appeal to an international audience and boost sponsorship
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Deal includes shared merchandise sales, advertising space and sports scientists
"We felt that this @placeholder team, the fourth oldest of the existing teams, reflects our own ideals perfectly," Chelsea chief executive Ron Gourlay said.
"We felt that this Swiss team, the fourth oldest of the existing teams, reflects our own ideals perfectly," @placeholder chief executive Ron Gourlay said.