ON SUNDAY night, with three rounds left in the super- grandmaster tournament in Sarajevo, there were four joint leaders - Bareev, Shirov, Kasparov and Michael Adams on 4/6 - then Morozevich 3.5, Topalov 3, Leko and Short 2.5, Ivan Sokolov 1.5 and Timman just 1.

Despite the traffic jam at the top it has been a magnificently competitive event, with 16 of the 30 games (25, omitting the hiatus in round four when all five games were drawn) ending decisively; indeed on three days there was just a single draw.

The absolute maximum excitement, thus far, was in round three last Wednesday which included this rousing struggle.

If 12 ...Nxe3 13 Qxe3 White has a lot of pressure against the Black queenside which at least compensates for his weak c3 pawn. Both players "went for it", with Short bravely inviting Kasparov to sacrifice first with 15 c4 and then 18 Bxh6.

Not 24 ...Qc3? 25 e5! Qxa3? 26 Be4 Be8 27 Rh5 and mates but 30 ...Bc6!? may be an improvement.

The crisis came after 32 Qh4 when 32 ...Bxg6 is a big improvement. Then:

a) The obvious 33 Qg4 runs into Kf7 34 Rb3 Rh8 35 Bxg6+ Rxg6 36 Rf3+ Ke7! 37 Rxg6 Qa1+ 38 Kg2 Qh1 mate!

b) So 33 a4 looks best when if Kf7 34 a5 Rh8 35 Rxg6 Rxg6 36 Bxg6+ Qxg6 37 Qf4+ Kg8 38 Qb8+ leads to perpetual check.

White: Garry Kasparov

Black: Nigel Short

Nimzo-Indian Defence