The phrase "in the ballpark" usually refers to something that is close to the correct or estimated number, amount, or range. Some of the antonyms for this phrase could include "off the mark," "way off," "nowhere near," or "out of range." These phrases suggest that the estimate or guess made is wildly inaccurate or completely wrong. Other possible antonyms for "in the ballpark" could include "unrelated," "irrelevant," or "misleading," which may suggest that the topic or assumption being discussed is not relevant, applicable, or accurate in the given situation. The antonyms of "in the ballpark" indicate inaccuracy, irrelevance, or incorrectness, while the original phrase suggests proximity or accuracy.