Jonathan Penrose, who has died aged 88, won the British chess championship a record 10 times, and in 1960 was the first English player for 61 years to defeat a reigning world champion. Yet he always remained an amateur, whose chess career was fitted into vacations at Middlesex University, where he lectured in psychology.
Penrose’s special moment came at the Leipzig Olympiad when he resoundingly beat Mikhail Tal in the only game that the USSR gold medal team lost all tournament. He characteristically understated his achievement, describing his feelings as “like playing an Essex v Middlesex county match”.
That morning he had studied a newly published game that Tal’s teammate Paul Keres had lost to the Finnish master Kaarle Ojanen a few weeks earlier in the world champion’s favourite defence. Penrose was so impressed that he decided to drop his normal king’s pawn opening 1 e4 in favour of the queen’s pawn 1 d4, to provoke Tal’s Modern Benoni.
The strategic concept was simple. When Tal, following one of his own previous wins, moved a rook from f8 to e8, Penrose unleashed a pawn sacrifice which enabled the Englishman’s queen and rook to breach the black defences via the the vacated f1-f8 line. Tal fell acutely short of time, lost a piece, belatedly resigned, and blamed Keres.
The game created a furore because of its decisive style and its dent to the Soviet team’s invincibility. Penrose was given a standing ovation when he entered the players’ dining hall that evening, and next morning the Guardian and other English broadsheets headlined the result on their front pages.
Penrose actually scored two wins and a draw against world champions at Leipzig. He outplayed the former holder Max Euwe of the Netherlands, then caught Bobby Fischer’s king in mid-board, forcing the American to settle for an endgame a pawn down. Short of time, Penrose offered a draw, Fischer replied “Sure!”, then demonstrated a forced win for Penrose.
Penrose was born in Colchester, Essex, the third son of the geneticist Lionel Penrose and his wife, Margaret (nee Leathes), a medical specialist. Jonathan’s siblings, Oliver, Roger and Shirley, all became distinguished academics; Roger was awarded a Nobel prize for his work on black holes and relativity.
Jonathan learned chess at the age of four, and soon displayed unusual talent. He was the British under-18 champion at 13 and London champion at 15, then defeated the former world title challenger Efim Bogolyubov in his first international tournament, at Southsea, Hampshire, in 1950.
In that year’s British championship, he beat the 1948 winner, Reginald Broadbent, in the very first round, after which Broadbent cautioned him about spending too much time on chess at the expense of his studies and career. Penrose heeded the warning, and his progress slowed in the next few years as he gave priority to his degree and doctorate in pyschology at London University.
His next breakthrough came with his first British championship in 1958. It was the first of six successive titles, and coincided with his playing peak at both Leipzig and the next Olympiad in 1962 at Varna, Bulgaria, where he amassed 12.5/17 on top board for England. Then he narrowly missed qualifying for the later stages of the world championship at the 1963 zonal tournament. A further run of four British titles from 1966 to 1969 broke Henry Atkins’s longstanding record of nine wins, while at the 1968 Olympiad in Lugano, Switzerland, his unbeaten 12.5/15 total on top board was second only to the world champion Tigran Petrosian.
In 1970 he fainted twice at the board, first at Ilford and then, following a blunder, at the Olympiad in Siegen, Germany. He soon returned to action, but his results dropped well below those of his peak years. Nice 1974 was his final Olympiad, while in the 1977 British championship he was beaten by the new prodigy Nigel Short, then just 12.
Penrose was grandmaster strength, though he only held the lesser international master title. The global body Fide refused his GM application in 1978, but in 1993 his friend Bob Wade, himself a British champion, was a member of the Fide qualifications committee and successfully renewed the bid.
After giving up over-the-board play, Penrose became very successful at correspondence chess, where at one time he was ranked No 1 in the world. Eventually he abandoned that, too, and for most of his last decade played social bridge at his local club in Welwyn, Hertfordshire.
Penrose was soft-spoken, with a slight transatlantic accent dating back to his war years as a child, spent in Canada. His demeanour at the board was invariably quiet and calm, with flushed cheeks during time pressure the only sign of inner tension. The company of colleagues sparked his creativity, and his best results were all in team events, notably for England in the biennial Olympiads but also including club and county games for Hampstead and Essex, or when his friends were present.
His earliest attempts at the British title brought mixed results, so for the 1958 event he formed a collective and stayed at the same guest house as Peter Clarke and myself, where we spent the mornings preparing and the evenings in post-mortems. This arrangement continued until 1961, and Penrose won all four titles.
He was less successful in travelling on his own to the top overseas tournaments, which he only tried twice, at Mar del Plata, Argentina, in 1962, and Palma de Mallorca, Spain, in 1969. In both, he began well, and was in mid-table until the closing rounds.
Penrose’s playing style was generally classical and logical, in the tradition of José Capablanca and later of Anatoly Karpov. He was better with the white pieces, where he used the solid Ruy Lopez against strong opponents and the unfashionable Goring Gambit, which he had studied in depth, against lesser lights. He was made OBE in 1971 for services to chess.
In 1962, he married Margaret Wood, who was a British ladies’ championship competitor. They separated in 1978. Their daughters, Katy and Harriet, survive him.
• Jonathan Penrose, chess grandmaster, born 7 October 1933; died 30 November 2021