MADRID (Reuters) - The head of Goldman Sachs ( GS ) 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 ( GS ) for 26 years, was responsible for the expansion of the investment banking franchises in Spain and Portugal.

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

In its memo sent to staff on Monday, Goldman Sachs ( GS ) 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' ( GS ) debt financing activities in Iberia and client coverage responsibilities in Portugal.

($1 = 0.9527 euros)

(Reporting by Jesús Aguado)