THE ONYX-Leigh Grand Prix is building up nicely - nicely, that is, for those of us not directly involved - towards the traditional bloody climax at the Islington Open on the last weekend before Christmas.

Despite his relative failure at Grangemouth two weekends ago, in which a loss to Scottish grandmaster Colin McNab led to a total of "only" 4/5, Jim Plaskett has racked up no fewer than four perfect scores in the last two months with the latest 5/5 at the West Wales Congress last weekend. His extraordinary industry has now brought him to within a point of the leader, Mark Hebden, in the race for the pounds 3,000 first prize.

Meanwhile Keith Arkell scored 6.5/7 at the traditional Paignton tournament, played at the extremely civilised rate of one round a day last week, to better his claim. As they enter if not the finishing straight then at least the final lap, the top scores are: Hebden 185.3/200, Plaskett 184.8, Arkell 177.9.

It is likely that the winner will be one of these three, but this is far from certain because all have played in a large number of tournaments. According to the complex formula that governs this event, it is much easier to better one's score if one has played less thus far; and so even players such as McNab - currently 14th on just 128.3 points - might have a chance if they take to the road or hit it lucky in Islington, in which results are multiplied eightfold to a maximum of 40 over the five rounds, so as to keep suspense to the very end.

Jonathan Rowson

(Black to play)

Jim Plaskett (White)

The above diagram shows the often rather manic Plaskett in much more controlled form in his fine win against Jonathan Rowson at Grangemouth.

His performance was particularly impressive as pawn endings are notoriously difficult, with just a single slip often leading to irreparable harm.

Here 34...g4?? was desperate. Rowson should have 34...Kg7!. The main line goes 35 c4 Kh6 36 b4 Kxh5 37 c5 Kg6 when it's vital that 38 b5? Kf6 is bad for White. Instead 38 Ke5! h5 39 b5 Kf7 40 Kd6! g4 41 fxg4 hxg4 42 c6 bxc6 43 bxc6 g3 44 c7 g2 45 c8Q g1Q 46 Qxe6+ leads to a draw.

The actual game moves are as follows: 34...g4?? 35 fxg4 Kg5 36 Kf3 e5 37 c4 e4+ 38 Kxe4 Kxg4 39 b4 Kxh5 40 Kf5 Kh4 41 c5 a6 42 a4 h5 43 b5 axb5 44 axb5 Kg3 45 c6 bxc6 46 b6 resigns