4.Bxf6 must come into consideration here, but best is probably 4.d4 to prevent Black playing e5.

4... e5 5. d3 Be7 6. Bg2 O-O 7. O-O Nc6 8. e3 Qe8 9. c4 f4 10. exf4 exf4 11. Nc3 Qh5 12. Ne2 fxg3 13. Nxg3 Qe8

Clarke's original intention was to play 13...Qh6 but he was concerned that after 14.Bc1 Qg6 his Queen might be short of space. A good plan for White might then be Re1, Nh4 and Nhf5.

14. Qd2 Nh5 15. Rae1 Nf4 16. Re4 Qf7

Black has now a superior position. The immediate threat is 17... Nxg2 18.Kxg2 Qxf3+ winning a piece. Esmonde decides to react tactically.

17. Bxg7

Clarke had considered this move in other variations, but not in this particular position. Now 17...Nxg2 does not work because of 18.Bxf8. Capturing the Bishop doesn't work either: obviously 17...Qxg7 allows 18.Rxf4 and White gains a pawn while 17...Kxg7 18.Rxf4 and if now 18...Qxf4 19.Nh5+ winning the Black Queen.

17... Nh3+

But this move cuts across White's plans.

18. Bxh3 Bxh3

Now 19.Bxf8 loses to Qxf3.

19. Ng5

19.Qh6 might have been worth a try. Although 19... Qxf3 20.Qxh3 Kxg7 leaves Black a piece up, the plausible 19...Qxg7 is met with 20.Qxh3 Rxf3 21.Rxg4 Bg5 22.Qh5 h6 23.Rxg5! (but not 23. h4 Ne5!) Qxg5 24.Qxf3 and White comes out a pawn ahead.

19... Bxg5

Not 19...Qxg7 because of 20.Nxh3.

20. Qxg5 Qxg7 21. Qd5+ Kh8 22. Rfe1 Ne5

Hardly a premature resignation against a player of Clarke's ability but one possible variation 23.R1e2 Nxf3+ Kh1 Qa1+ shows just how much trouble White is in.

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