The aim of the study was to investigate the influence of teacher pedagogy in improving tertiary level students’ English writing skill and self-perceptions. The purpose was to determine how far an eclectic approach to teaching English writing skill can be of assistance in developing the writing skill and confidence of bilingual speakers of English at tertiary level. This study employed pre/post-test and quasi experimental research design. The sample consisted of 66 students of English at Bachelor’s level and two teachers in a government college of Lahore, Punjab. The students were placed into two groups. The experimental group was taught by a TESL trained teacher and the control group was taught by a regular teacher. Both groups wrote an essay and completed questionnaires at the beginning and end of the study. After nine months of teaching writing skill, the pretest and posttest essay and questionnaire scores of the groups were compared using independent and paired sample T-tests and Hedges’ g to calculate the effect size of the change. Both teachers’ classroom lessons were analyzed through observation. Evidentially, eclectic approach had significant positive effect on students’ overall performance in essay writing and self-perception. Keywords: Eclectic Approach - Product Approach - Process Approach - English Writing Skill, Self-perception, Teaching English as Second Language (TESL)