It's an interesting topic. What I have learned from the spiritual sciences is that this type of intention around competition will produce negative karma. Healthy competition, in other words, playing the game without manipulation, for the sake of the game and to improve your performance, produces "good" karma.
If someone is trying to rip you off, it is appropriate to be angry, there is no negative karma produced. But in the case above and when the intention is to do harm, then negative karma will weigh on the soul, producing tension and dullness.
I've learned a valuable trick. When you have negative thoughts about someone or something, throw it back to the Universe. Tell the Universe to take the thoughts away from you and you will feel it dissolve, your soul will be lighter for it. Try it.