A glimpse into the past: the story of a picture
3.5 As the table shows, Alekhine did not suffer a single loss, whereas Schmidt lost two games: one against Georg Kieninger and one against Alekhine. The two later tournament winners, Schmidt and Alekhine, met each other in the fourth round and in this game Schmidt had what he later described as his most "unforgettable chess experience". According to Schmidt, Alekhine in this game "moved a rook and just took the move back". (See Eva Regina Magacs, Michael Negele, Paul Felix Schmidt: A Winning F...
Source: chessbase.com