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The 1981 Madrid Grand Prix was a men's tennis tournament played on outdoor clay courts that was part of the 1981 Volvo Grand Prix tennis circuit. It was the 10th edition of the tournament and was held at the Real Sociedad Hípica Española Club de Campo in Madrid, Spain from 28 September until 4 October 1981. First-seeded Ivan Lendl won the singles title.
It was Gómez' 5th doubles title of the year and the 10th of his career. It was Gildemeister's 3rd doubles title of the year and the 10th of his career.
John Barrett, ed. (1982). Slazengers World of Tennis 1982 : The Official Yearbook of the International Tennis Federation (14th ed.). London: Queen Anne Press. pp. 28, 123. ISBN9780356085968.
Ivan Lendl
Andrés Gómez / 
Hans Gildemeister
Pablo Arraya 6–3, 6–2, 6–2
Heinz Günthardt /