As a young man, he was a high achiever, principally as part of the USSR's highly successful Student Olympiad team of 1954–1956. The team won the silver medal at the first-ever Student Olympiad in Oslo 1954 and then took gold medals at Lyons 1955 and at Uppsala 1956. His best performance probably occurred at Lyons, as the strength of the competition was far greater than at Oslo. Playing below world-class grandmasters Mark Taimanov and Boris Spassky, but above Alexey Suetin, his endeavors also earned him an individual gold medal for best score on board three. In all, he accumulated three gold and one silver medal, for a total score of 16/19. During this period of his career, FIDE awarded him the International Master title and the Grandmaster title.
Later career
Making a limited number of international tournament appearances, he was successful at Ulan Bator and Zinnowitz. The latter was probably his finest moment, scoring +8−1=6, to take first place among reasonably strong opposition, including Victor Ciocaltea and Wolfgang Uhlmann. Aside from Zinnowitz, Hartston notes that Antoshin's results were never outstanding. His other results were nevertheless respectable; 2nd at Kienbaum 1959, 5th at Moscow 1960, 4th at Sochi 1963, 4th at Moscow 1963, 6th= at Sochi 1964, 2nd at Venice 1966 and 4th at Havana 1968. He regularly played at Sochi, but finished lower on other occasions. His tournament appearances were less frequent in the 1970s. He did, however, share 3rd place at Sarajevo in 1970 and placed runner-up at Frunze in 1979. A major reason for his limited progress as a player was his continued amateur status. He became a tournament organiser and trainer to the USSR Olympiad team, maintained a second career as a technical designer, and according to Cafferty & Taimanov, was also supposed to have strong links with the KGB. As a further distraction, he chose to play correspondence chess throughout the 1950s, although this notably culminated in him winning the USSR Correspondence Championship in 1960. At the Soviet Championship, he had moderate results, participating in 1955, 1956, 1957, 1967 and 1970. His highest placing was a share of sixth in 1967.
In the Antoshin Variation, Black chooses to exchange central pawns and head for simple, rapid development of the kingside. After...0-0 and...Re8, Black's cramped dark-square bishop is often reactivated by playing it to g7 via f8. Play commences, and White usually chooses to develop one of his bishops, for example: with a small advantage to White in Hyldkrog–Jensen, corr. 1984. The opening remains fully playable, however, with modern-day proponents including Lev Aronian, Étienne Bacrot and Liviu-Dieter Nisipeanu.
Dutch Defence
The Hort–Antoshin Variation was first discovered by Vlastimil Hort in 1960, when he was just 16; it was then further developed by Antoshin and consequently carries the names of both players. Black's idea is to omit the 'normal'...e6 move and prepare a central break with...e5 instead. The line may also be used with 'colours reversed' as a variant of Bird's Opening where White is a move up. Play starts, Burgess gives the more modern alternative 4.Nc3 c6 5.e4 fxe4 6.Nxe4 Nxe4 7.Bxe4 Bf5 8.Qf3 Bxe4 9.Qxe4 Qa5+ 10.c3 as favouring White in Khenkin–Vasiukov, Voskresensk 1990. whereupon, one possible continuation is the direct: which ended in an early draw in Minev–Hort, Moscow 1960.
Notable games
Black hits his opponent with successive pawn and exchange sacrifices, in order to open lines towards the enemy king.
