Complex sentence: To do this, she must cause attendance at the games to fall below a certain level so she decides to replace existing players with aging veterans and inexperienced rookies in the hopes that a bad team will cause attendance to decline.
Split into simpler sentences: To do this, she must cause attendance at the games to fall below a certain level. She decides to replace existing players with aging veterans and inexperienced rookies in the hopes that a bad team will cause attendance to decline.