Field-based observation has long been a central part of pre-service teacher education in many countries and is crucial for implementing effective practicum of pre-service teachers. This paper focused on the perspectives of graduating pre-service teachers regarding their difficulties related to administrative support, cooperating teachers, student supervisors, students, peers, assigned tasks and learning environment during their 17-hour field observation in selected private and public secondary schools. An explanatory sequential mixed-methods research design was adopted utilizing survey questionnaire, Focus Group Interviews, and Key Informant Interview. Quantitative data were obtained from 136 sample respondents through stratified random sampling using proportionate allocation while qualitative data were gathered from 10 pre-service teachers, 10 cooperating teachers, six student supervisors and two school principals who were chosen purposively. Results of descriptive statistical analysis served as basis for the design of qualitative interview and focus group schedules which helped the researcher to "explain, or elaborate on the quantitative results". Findings of the study showed that pre-service teachers had over-all moderate difficulties during the field observation particularly on students, assigned tasks and learning environment. Findings of the study were substantiated through in-depth discussions of qualitative data. Implications were determined for continued enhancements of the practicum component that can help bridge the theory-practice nexus in pre-service teacher education, and contribute to the development of teachers' professional competencies.