The goal of this thesis was to evaluate the probability of the favourite winning in different competitions and answer the question which competition is the best. The best in this case meaning the competition that gives the best team the highest chance of winning. Tournament systems that were realized are league, elimination tournament, and combined tournaments. Also implemented are different ways of determining opponents. These are draw, seeding, and re-seeding. Java was used as the programming language. On the basis of sufficient number of simulations run, we acquired estimations that are good enough to get a good idea of the probabilities of the favourite winning in various tournament systems. In the end, we conclude that the best competition is the league.