Mario, a Professional Entertainer, Entered into a One-Year Contract with Barnum

Mario, a professional entertainer, entered into a one-year contract with Barnum to perform exclusively at Barnum's theatre and nowhere else during that period of time. A week after the agreement was signed, Mario entered into another agreement with a competitor of Barnum to perform at his opera house. Barnum is entitled to treat Mario's actions as a breach of his contract.