Blended learning (BL) is probably the most widely used approach in higher education, with characteristics that make it an excellent way to introduce a paradigm shift. This paper analyses the beliefs, expectations and attitudes of university teaching staff regarding the acceptance - and adoption - of BL methodologies from a quantitative and qualitative perspective. A mixed-method design (a sequential explanatory model) was used. Furthermore, a confirmatory factor analysis of the technology acceptance model (TAM) and a topic analysis were also carried out. A sample of 982 Spanish university lecturers participated in the study, with 86 taking part in the qualitative analysis. The results show that the variable intention essentially determines the lecturers' acceptance of the use of BL. Furthermore, a series of opinions (advantages and disadvantages), as well as these lecturers' main demands, are related to the implementation of BL. The positive aspects were practice-based cases, the improvement of digital skills, peer learning, and greater interaction. The negative ones were related to time and effort, little coordination among teachers, higher classroom ratios, and difficulties in tracking the submission of assignments.