A growing number of stakeholders in teacher education in Nigeria have raised concerns about the quality of mentoring in schools. In this study, we aim to explore the mentoring experiences of student teachers during their field experiences. Using a mixed-methods study, data were collected from student teachers in the education faculty at a University in Nigeria. Quantitative data on student-teacher mentoring experiences were collected using the Student-Teacher Mentoring Experience Questionnaire. Qualitative data comprised individual interviews and was analysed thematically. Findings indicated that student teachers lacked adequate mentoring and support and without timely evaluations and quality feedback, their ability to reflect critically on practice was compromised. It was recommended that stakeholders in tertiary institutions adopt more robust and comprehensive mentoring policies for student teachers. Strengthening school-university partnerships and conducting professional mentor training focused on co-constructing knowledge through communication and collaboration is vital. Without these measures, student teachers will remain on the periphery of the teaching community.