Mikhail Botvinnik vs Mikhail Szebarszin
Olympiad of Leningrad-group 5 Leningrad URS 1926.05.??
King’s Indian Defense: Kazakh Variation 1-0

Mikhail Szebarszin vs Alexey Sokolsky
3rd Ch RSFSR Moscow (URS) 1928.11.??
Queen’s Gambit Declined: Orthodox Defense, Alekhine Variation 1-0