Andrejs Petersons vs Karlis Klasup
LAT-ch Riga LAT 1952.??.??
Slav Defense 0-1

Alexander Koblents vs Karlis Klasup
Riga championship Riga LAT round 2 1958.??.??
Queen’s Gambit Declined: Tarrasch Defense 1/2-1/2

Karlis Klasup vs Mikhail Tal
LAT-ch URS 1952.??.??
Semi-Slav Defense: Bogoljubov Variation 0-1

Karlis Klasup vs Alexander Koblents
Latvian championship Riga LAT 1963.??.??
King’s Indian Defense: Fianchetto Variation, Classical Main Line 0-1