The only match played under those rules was Capablanca vs Alekhine in 1927, although there has been speculation that the actual contract might have included a "two-game lead" clause. Alekhine, Rubinstein and Nimzowitsch had all challenged Capablanca in the early 1920s but only Alekhine could raise the US$10,000 Capablanca demanded and only in 1927. Capablanca was shockingly upset by the new challenger. Before the match, almost nobody gave Alekhine a chance against the dominant Cuban, but Alekhine overcame Capablanca's natural skill with his unmatched drive and extensive preparation (especially deep opening analysis, which became a hallmark of most future grandmasters). The aggressive Alekhine was helped by his tactical skill, which complicated the game.