| Game |
| Result | Moves |
Year |
Event/Locale | Opening |
| 1. I Papaioannou vs T Gelashvili |
| 1-0 | 44 |
1999 |
Chania op 9th | E06 Catalan, Closed, 5.Nf3 |
| 2. I Papaioannou vs Beliavsky |
| ½-½ | 31 |
2000 |
34th Olympiad | E05 Catalan, Open, Classical line |
| 3. I Papaioannou vs Ehlvest |
| ½-½ | 29 |
2000 |
34th Olympiad | E06 Catalan, Closed, 5.Nf3 |
| 4. I Papaioannou vs J Gonzalez |
 | 0-1 | 35 |
2004 |
36th Olympiad | E06 Catalan, Closed, 5.Nf3 |
| 5. I Papaioannou vs N Skalkotas |
| 1-0 | 28 |
2005 |
34th Greek Teams Championship | E05 Catalan, Open, Classical line |
| 6. I Papaioannou vs G Van der Stricht |
| ½-½ | 43 |
2005 |
15th European Team Championship | E04 Catalan, Open, 5.Nf3 |
| 7. I Papaioannou vs V Iordachescu |
| 1-0 | 40 |
2006 |
37th Chess Olympiad | E05 Catalan, Open, Classical line |
| 8. I Papaioannou vs S Azarov |
| 1-0 | 35 |
2008 |
2008 Olympiad | E06 Catalan, Closed, 5.Nf3 |
| 9. I Papaioannou vs L F Ibarra Chami |
| 1-0 | 52 |
2008 |
2008 Olympiad | E04 Catalan, Open, 5.Nf3 |
| 10. I Papaioannou vs Beliavsky |
| ½-½ | 24 |
2009 |
17th European Team Championship | E06 Catalan, Closed, 5.Nf3 |
| 11. I Papaioannou vs Tiviakov |
| 1-0 | 60 |
2009 |
10th European Individual Championship | E01 Catalan, Closed |