This week’s puzzle marks the opening round of a national competition in which Guardian readers have traditionally performed strongly over many years.
You have to work out how White, playing as usual up the board in the diagram, can force checkmate in two moves, however Black defends.
The puzzle is the first stage of the Winton British Chess Solving Championship, organised by the British Chess Problem Society and open to any British resident. Entry is free, and the prize fund will be at least £1,225.
If you would like to take part, simply send White’s first move to Nigel Dennis, Boundary House, 230 Greys Road, Henley-on-Thames, Oxon RG9 1QY or by email to [email protected].
Either way, please include your name and home address, and mark your entry “Guardian”. If you will be under 18 on the closing date, 31 July, please also give your date of birth. After the closing date, all solvers will receive the answer and those who get it right will also be sent a postal round of eight problems, with plenty of time for solving.
The best 25-30 entries from the postal round, plus the best juniors, will qualify for the one-day final to be staged in February 2020. The winner there will qualify for the 2020 world solving championship.
As usual, the starter problem is tricky with all the action in the top half of the board. There are several plausible near-misses and White’s first move is not obvious. Remember that routine checks and captures rarely work in composed problems. It is easy to make an error, so review your answer before sending it. Good luck to all Guardian entrants.
Just 12 days after scoring his seventh straight tournament victory at Stavanger, world champion Magnus Carlsen will be in action again in another very tough event. The Zagreb, Croatia stage of the Grand Chess Tour starts at 3.30pm BST next Wednesday, 26 June.
Most GCT events have 10 Tour players, but Zagreb has all 12, of whom nine currently rank in the world top 10 in the live ratings. The city itself is steeped in chess history, hosting Zagreb 1955 won by Vasily Smyslov, Zagreb 1959 the middle leg of the candidates won by Mikhail Tal, and Zagreb 1970 won by Bobby Fischer.
Playing and winning seven tournaments in six months is a fierce schedule by the standards of previous world champions, so there is a risk of Carlsen running short of stamina in Zagreb.
He was strong at Wijk aan Zee, Shamkir, Grenke and Abidjan but less convincing in his last two tournaments at Lindores Abbey and Stavanger, where he described his own performance as “mediocre” despite his three-point winning margin.
On the plus side, Carlsen’s current live rating of 2872.5, losing just 2.5 rating points in Norway, is within sight of his own all-time rating records of 2882 (official monthly) and 2889 (daily) and even of a round 2900, landmarks which he calls “at least a half-attainable dream”.
England’s current No 1 and No 2, Gawain Jones and David Howell, are both competing in the $40,000 St Louis Summer Classic, a highly rated six-GM double round event. Howell took the round one lead, defeating the 2018 US champion Sam Shankland with Black in 85 moves. The games are free and live to watch online from 7pm BST daily. After Thursday’s third round (of 10), Jeffery Xiong (US) and Howell led on 2/3, followed by Dariusz Swiercz (US) and Jones 1.5.