Iterated Weak Dominance in Strictly Competitive Games of Perfect Information

We prove that any strictly competitive perfect-information two-person game with n outcomes is solvable in n-1 steps of elimination of weakly dominated strategies - regardless of the length of the game tree. The derivation is based on the fact that if player i does not possess a winning strategy, then any of player j's strategies that enables i to win is eliminated by two steps of iterated dominance. The given bound is shown to be tight using a variant of Rosenthal's centipede game.