Despite the growing interest in work engagement crossover among employees, we still need more research about the role of the supervisors’ work engagement on employees’ states and behaviors. This study examines the relationship between the supervisors’ work engagement and the employees’ work engagement. We also investigate how supervisors’ and employees’ work engagement relate to employees’ in-role and organizational citizenship behavior (OCB). Finally, we explore the mediating role of employees’ affective commitment linking employees’ and supervisors’ work engagement to employees’ performance. To test the proposed model, we performed multilevel models with a sample of 570 employees nested around 88 supervisors from 7 organizations in Ecuador. Results show that supervisors’ work engagement is not related to employees’ work engagement. Employees’ affective commitment partially mediates the relationship between employees’ work engagement and performance, whereas employees’ affective commitment fully mediates the relationship between supervisors’ work engagement and employee performance. Thus, employees’ emotional attachment significantly impacts employee performance (in-role and organizational citizenship behavior) among engaged employees.