New York 1924: Reti vs Capablanca RND 5
Here is the score sheet of the this famous upset ( apologies to my comraderie at the J.R. Capablanca group. Soon I will highlight his play as I cover this series)
Capablanca was in the midst of an eight year long 63 game unbeaten streak (his last loss was to Chajes at New York 1916). Reti ended this run in the fifth round, when Capablanca went badly wrong on the black side of a hypermodern Reti opening. He got his queen stuck in the mud. Experts say this was the wake up call he needed and came back fighting for the remaining rounds.