Game |
| Result | Moves |
Year | Event/Locale | Opening |
1. J Siska vs M Grencarski |
| 1-0 | 32 | 1935 | Yugoslav Amateur Championship sf-A | D11 Queen's Gambit Declined Slav |
2. I Lesnik vs J Siska |
| 1-0 | 35 | 1938 | Yugoslav Amateur Championship | B72 Sicilian, Dragon |
3. J Siska vs A Jonke |
| 1-0 | 28 | 1938 | Yugoslav Amateur Championship | A95 Dutch, Stonewall |
4. D Avirovic vs J Siska |
| 1-0 | 28 | 1938 | Yugoslav Amateur Championship | E43 Nimzo-Indian, Fischer Variation |
5. V Medan vs J Siska |
| 0-1 | 54 | 1939 | Yugoslav Amateur Championship sf-A | C22 Center Game |
6. J Siska vs M Atijas |
| 1-0 | 34 | 1939 | Yugoslav Amateur Championship sf-A | E43 Nimzo-Indian, Fischer Variation |
7. J Siska vs Gligoric |
| 0-1 | 62 | 1939 | Yugoslav Amateur Championship sf-A | E49 Nimzo-Indian, 4.e3, Botvinnik System |
8. J Siska vs I Jerman |
| 1-0 | 53 | 1939 | Yugoslav Amateur Championship sf-A | B32 Sicilian |
9. J Siska vs J Feuer |
| 1-0 | 53 | 1939 | Yugoslav Amateur Championship sf-A | A35 English, Symmetrical |
10. Gligoric vs J Siska |
| 1-0 | 66 | 1939 | Yugoslav Amateur Championship | D61 Queen's Gambit Declined, Orthodox, Rubinstein Attack |
11. M Subaric vs J Siska |
| 1-0 | 41 | 1939 | Yugoslav Amateur Championship | D96 Grunfeld, Russian Variation |
12. J Siska vs J Sorli |
| 0-1 | 26 | 1939 | Yugoslav Amateur Championship | E34 Nimzo-Indian, Classical, Noa Variation |
13. I Jerman vs J Siska |
| 1-0 | 37 | 1939 | Yugoslav Amateur Championship | A93 Dutch, Stonewall, Botvinnik Variation |
14. F Zuk vs J Siska |
| 0-1 | 39 | 1940 | Yugoslav Amateur Championship | A48 King's Indian |
15. G Berner vs J Siska |
| ½-½ | 36 | 1940 | Yugoslav Amateur Championship | E48 Nimzo-Indian, 4.e3 O-O 5.Bd3 d5 |
16. B Savic vs J Siska |
| 0-1 | 40 | 1940 | Yugoslav Amateur Championship | A04 Reti Opening |
17. M Mlinar vs J Siska |
| 0-1 | 41 | 1940 | Yugoslav Amateur Championship | D51 Queen's Gambit Declined |
18. J Siska vs I Kindij |
 | 0-1 | 32 | 1946 | Yugoslav Semifinal West | C18 French, Winawer |
19. F Licul vs J Siska |
| 1-0 | 29 | 1946 | Yugoslav Semifinal West | E80 King's Indian, Samisch Variation |
20. J Siska vs S Georgijevski |
| 1-0 | 24 | 1947 | Yugoslav First League | A07 King's Indian Attack |
21. I Lesnik vs J Siska |
 | 0-1 | 31 | 1948 | Rogaska Slatina | B76 Sicilian, Dragon, Yugoslav Attack |
22. D Timet vs J Siska |
| 1-0 | 30 | 1948 | Yugoslav First League | D08 Queen's Gambit Declined, Albin Counter Gambit |
23. J Siska vs M Jovcic |
| 0-1 | 45 | 1954 | Yugoslav Semifinal West | D00 Queen's Pawn Game |
24. J Siska vs B Djurasevic |
| 1-0 | 41 | 1956 | Yugoslav First League | E55 Nimzo-Indian, 4.e3, Gligoric System, Bronstein Variation |
25. J Siska vs M Damjanovic |
| 0-1 | 38 | 1958 | Yugoslav First League | E76 King's Indian, Four Pawns Attack |