The first use of such a rule was in a tournament in London in 1883, but was stated vaguely: "... if a series of moves be repeated three times the opponent can claim a draw." The rules for the first official World Chess Championship 1886 match between Wilhelm Steinitz and Johannes Zukertort stated: "... if both players repeat the same series of moves six times in succession, then either player may claim a draw." In two of the games the same position was repeated three times. The rule was modified soon afterward to be based on positions instead of moves, and for three repetitions . Draws by this method used to be uncommon .