Riddle: Botvinnik–Boleslavsky, 1943

Mikhail Moiseyevich Botvinnik is undoubtedly one of the towering figures in the entire history of chess, from the birth of modern chess (circa 1495) to the present day. The subject of this article is a game Botvinnik played in 1943 (while World War II was still raging) against one of the great hopes of Soviet chess at the time – and a true innovator – Isaac Boleslavsky. Botvinnik awarded his pawn sacrifice in the middlegame an exclamation mark in all his annotations. But was he correct? | Help us unravel this riddle.