This study investigates perceptions and practice of the roles of EFL (English as a foreign language) teachers at two Vietnamese universities in their blended English classes. Blended language learning (BLL) is often understood as a combination of face-to-face (F2F) learning and computer-assisted language learning (CALL). Teachers play an essential role in technology implementation in language education. Understanding their reality is vital for sustainable change. The study builds on theoretical models of teacher roles and blended learning. It draws on qualitative data. The six teachers in this study successfully combined traditional roles with innovative ones in the new learning environment. They became independent and creative designers, thus facilitating the blend of F2F and online learning. Nevertheless, they experienced challenges in designing activities for the successful complementarity of the blend. This study underlines the need for a high(er) level of teacher autonomy and professional learning opportunities for effective pedagogical practice in BLL in the Vietnamese context, other Confucian heritage culture countries such as China, Singapore, Korea, and Japan, and beyond. Such changes will pave the way for the success in improving English language capability and EFL teacher professional growth.