MADRID, March 3 (Reuters) - The head of Goldman Sachs GS.N in Spain and Portugal, Olaf Diaz-Pintado, will retire this summer and be replaced by two internal executives to allow for an orderly transition, according to an internal memorandum seen by Reuters.

Diaz-Pintado, who has worked at Goldman Sachs for 26 years, was responsible for the expansion of the investment banking franchises in Spain and Portugal.

In Spain, Goldman Sachs is advising Sabadell SABE.MC in its defence strategy against BBVA's BBVA.MC hostile takeover bid worth more than 12 billion euros ($12.60 billion).

In its memo sent to staff on Monday, Goldman Sachs said that Juande Gomez-Villalba and Gloria Carreno will assume additional responsibilities as co-heads of investment banking in Spain and Portugal upon Diaz-Pintado's retirement.

Gomez-Villalba and Carreno will work with Jorge Alcover, who will continue to lead Goldman Sachs' debt financing activities in Iberia and client coverage responsibilities in Portugal.

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(Reporting by Jesús Aguado)

((jesus.aguado@thomsonreuters.com; +34 91 835 68 32; Reuters Messaging: Reuters Messaging: jesus.aguado.reuters.com@reuters.net))