The final round game which decided the 2022 British championship at Torquay turned out to be a 75-move epic which had everything. Its protagonists were both Cambridge students: Harry Grieve, 21, mathematics, and Matthew Wadsworth, 22, economics. They were colleagues in their university chess club, but went for each other with zestful imagination in one of the best ever championship deciders.

A sharp opening with a material imbalance was followed by a knight retreat from f3 to its starting square g1, two exchange sacrifices, a winning king march, four queens on the board at the same time, and finally a queen sacrifice to force checkmate. It was a memorable encounter, worthy of its occasion.

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Nick Pert, the defending champion, was runner-up on 7/9, half a point behind Grieve, while Wadsworth tied for third.

First prize was £5,000, more than double the norm of recent years, due to sponsorship from the chess learning company Chessable, which is part of the world champion’s Play Magnus Group. That could enable Grieve, whose stellar result gave him his first grandmaster norm (three are needed), to test himself on the European circuit in the next few years. He and Wadsworth, who also has one GM result, will both be aiming for their second norms in the Northumbria Masters at Newcastle this weekend.

Another test will come when the Cambridge pair take on England’s 2600+ GMs who played at the Chennai Olympiad and who did not compete at Torquay due to the near-overlap of dates plus possible jetlag. It will not be a foregone conclusion by any means, since Grieve and Wadsworth have momentum and youth on their side.

Away from the British Championship, two performances stood out at opposite ends of the age scale. GM John Nunn was a class apart in the over-65s, winning all seven games effortlessly and only twice being taken to over 30 moves. Some thought that Nunn should have opted for the championship proper, but that would have been a severe stamina test. His final-round win was elegant.

Kushal Jakhria, who has featured previously in this column, impressed again in the Major Open. The seven-year-old from the Pointer School, Blackheath, and Charlton Chess Club scored 5.5/8, winning every game as White, until a stomach upset before the ninth and final round stopped him short of qualifying for the 2023 Championship with 6/9. That would have been a world age record, breaking David Howell’s 1999 mark by almost two years.

Jakhria is also in contention for another world mark. He has just under two months to reach a 2000 ECF national rating, and thus surpass Abhimanyu Mishra’s US record of becoming the youngest USCF Expert, also a 2000 rating, at seven years six months. Mishra went on to become the youngest ever grandmaster at 12. Can Jakhria do it? His current rating after Torquay is around 1950.

Over in Miami, Magnus Carlsen duly won the $210,000 FTX Crypto Cup, although the world champion had a decidedly rocky passage. He lost four games in one day to his Nemesis, Jan-Krzysztof Duda, and three in a day to the fast rising 17-year-old Indian, Rameshbabu Praggnanandhaa. At the finish the leading scores were Carlsen 16/21, Praggnanandhaa and Alireza Firouzja 15.

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Carlsen called his loss to Duda “a horrible day of chess” and more than once complained of fatigue. He now has a break until one of the most important tournaments of the year, the annual Sinquefield Cup, starts in St Louis on 1 September. There his opponents will include Ian Nepomniachtchi, the double Candidates winner who Carlsen recently refused to meet in a second world title match.

An all-grandmaster game ending decisively in 12 moves is a rare occurrence, but it happened in John Emms v Danny Gormally at Torquay after 1 e4 c5 2 c3 d6 3 d4 Nf6 4 Bd3 g6 5 dxc5 dxc5 6 e5 c4 7 Qa4+ Bd7 8 Qxc4 Ng4 9 f4 Nc6 10 Bc2 Qb6 11 Qe2 Nxh2 reaching the puzzle diagram where you have to find White’s 12th, which induced Black’s resignation.

3830: 12 Bb3! wins Black’s errant knight after 12...Bg4 13 Qe3 or 12...Ng4 13 e6!