Success in competitive environments hinges on complex psychological and social dynamics. In these contexts, performance can be disrupted when there is a mismatch between societal expectations and individual feedback competitors receive. This study examined how expectations tied to social identity influence physiological stress in competitive settings by manipulating aspects of a math competition task. Participants were randomly assigned to receive either negative or positive individual-level feedback, creating personal expectations of high/low performance on the upcoming task. To manipulate social expectations (i.e., based on social identity), competitions occurred in a same-sex, interracial dyad where one person belonged to a member of a racial group positively stereotyped in the mathematics domain (i.e., Asians) and the other was not (i.e., Whites). Asian participants exhibited greater sympathetic arousal, as evidenced by larger decreases in pre-ejection period (PEP), during both preparation and competition phases compared to White participants, suggesting heightened engagement in the competition task. Regardless of race, participants receiving negative personal feedback exhibited stronger physiological threat reactivity while anticipating the competition, compared to those who received positive feedback. Exploratory analyses examined moderation of effects by stress appraisals, group identification, and achievement goals. This study highlights the complex interplay between expectations, identity, and stress in competitive environments, providing insights into how psychological factors influence physiological outcomes.