[Event "Moscow IT"]
[Round "6"]
[Site "Moscow"]
[Date "1981.04.14"]
[White "Karpov, Anatoly"]
[WhiteElo "2690"]
[Black "Portisch, Lajos"]
[BlackElo "2650"]
[Result "1/2-1/2"]
[ECO "E41"]
[Opening "Nimzo-Indian, 4.e3 c5"]
 1. d4   Nf6
 2. c4   e6
 3. Nc3  Bb4
 4. e3   c5
 5. Nf3  O-O
 6. Bd3  d5
 7. O-O  dxc4
 8. Bxc4 Nbd7
 9. Qe2  a6
10. a4   Qc7
11. Na2  b5
12. Bd3  Ba5
13. axb5 axb5
14. Bxb5 Bb7
15. Rd1  Rfb8
16. h3   Bb4
17. Bxd7 Nxd7
18. Bd2  Bxd2
19. Qxd2 Bxf3
20. gxf3 Qb7
21. Kg2  Qxb2
22. Qxb2 Rxb2
23. dxc5 Nxc5
24. Nb4  Rc8
25. Nc6  Kf8
26. Ne5  Rb7
27. Nc4  Rbc7
28. Nd6  Rd8
29. Nb5  Rxd1
30. Rxd1 Rd7
1/2-1/2