This study developed a model of team mental models' influence on team adaptive performance at different stages. It proposed that mental models have different relationships with adaptive performance as a function of the performance stage when teams experience changes: early on (i.e., during situation assessment) more divergent mental models are needed for performance; later on (i.e., during plan execution) more convergent mental models are needed. The model was tested in an experiment with 33 teams (N= 99) faced with unforeseen change at task midway. Partially supporting the predictions of a divergence-convergence model, at situation assessment, teams that developed more dissimilar mental models attained a higher performance originality, but not higher efficiency or usefulness. However, at plan execution, team mental models' convergence did not lead to higher performance. Implications for research on team mental models are discussed.