"Am a par with" implies equality and equivalence. Therefore, antonyms for this phrase would include words that connote inferiority, such as "inferior," "subordinate," or "below-average." Other antonyms could include phrases that suggest being unequal or dissimilar, such as "incomparable," "unequal," or "dissimilar." Additionally, words that imply superiority, such as "excellent," "outstanding," or "superior," could also be considered antonyms for "am a par with." Ultimately, antonyms for "am a par with" will depend on the context and tone of the sentence in which it is used.