Nuchess (Computer) vs Belle (Computer)
3rd World Computer Championship Linz AUT round 2 1980.09.26
King’s Gambit Accepted: Abbazia Defense 1/2-1/2

Octavio Troianescu vs Gideon Stahlberg
Bucharest Bucharest ROU round 3 1954.03.01
English Opening: Anglo-Indian Defense, Grünfeld Formation 1/2-1/2

Ognjen Cvitan vs Norbert Sommerbauer
EU-chT (Men) Batumi GEO round 1 1999.11.29
Queen’s Gambit Accepted: Alekhine Defense, Borisenko-Furman Variation 1-0

Oksana Horoschavina vs Sunil Dhopade Swapnil
Albena Open Albena Resort, Albena Hall round 1 2012.05.26
Sicilian Defense: Canal Attack, Dorfman Gambit 0-1

Olaf Ulvestad vs Anthony Santasiere
New York ch-ACF New York, NY USA round 9 1939.07.26
King’s Indian Defense: Larsen Variation 0-1

Olavo Yepez Obando vs Robert James Fischer
Havana ol (Men) qual-C Havana CUB round 1 1966.10.26
King’s Indian Defense: Kazakh Variation 0-1

Oldrich Duras vs Alexander Flamberg
Mannheim Mannheim GER round 3 1914.07.22
Ruy Lopez: Berlin Defense, Closed Bernstein Variation 1-0

Oldrich Duras vs Geza Maroczy
Vienna Vienna AUH round 15 1908.04.11
Ruy Lopez: Morphy Defense, Anderssen Variation 0-1

Oleg Korneev vs Kamal Aghasiyev
Nakhchivan Open Nakhchivan AZE round 9.9 2014.05.12
French Defense: Tarrasch Variation, Chistyakov Defense 1/2-1/2

Oleg Loskutov vs Alexander Khalifman
Russia Team Championship Sochi RUS round 1 2004.04.20
Modern Defense 1/2-1/2