The study adopted an observational research design to assess the impact of the Split Teaching Practice Model on undergraduate pre-service teachers' performance in science content delivery within classroom settings, without researchers’ intervention. The population consisted of 119 second-year and 102 third-year science education students at Federal University Gusau - Nigeria, engaged in First and Second-phase teaching practice during the 2022/2023 academic session. A convenience sample of 96 pre-service teachers (54 in First-phase, 42 in Second-phase) was obtained. Data collection involved structured classroom observations using instrument tagged Pre-service Teachers' Performance in Science Content Delivery. Validity and reliability of the instrument were established through expert validation and inter-rater reliability assessment, yielding a correlation coefficient of 0.86. Four null hypotheses were tested using t-tests, focusing on lesson planning, presentation, class management, and attainment of objectives. The findings of the study revealed that, significant differences in favour of Second-phase pre-service teachers in aspects like sequential presentation, subject matter mastery, instructional materials usage, time management, and student participation. No significant differences were found in lesson introduction and questioning techniques. Second-phase pre-service teachers outperformed in class management and objective attainment. The study recommended continued adoption of the Split Teaching Practice Model, emphasizing refinement and customization to address specific improvement areas through feedback in teacher training institutions.