When a reservoir is bounded by one or more constant pressure boundaries, such as aquifer or gas cap, the main expectation of the production engineer is to delay the arrival of either water or gas into the well completed in the reservoir to optimize oil production. To achieve this expectation, it is important to understand fluid flow pattern through the reservoir system when oil is produced through the well. For a horizontal well, understanding the strategies to achieve optimum oil production in a reservoir subject to an edge water and bottom water acting simultaneously to provide drive energy in the reservoir poses challenges due to the complexity in well flow periods, aquifer activity and reservoir heterogeneity. In this paper, real time oil flow transient pressure model using dimensionless pressures and dimensionless pressure derivatives was developed using superposition principle and image method to investigate performance of a horizontal well subject simultaneously to single edge water and bottom water drive mechanisms. The model was tested to evaluate the horizontal well response to oil production transient flow for different well designs, reservoir anisotropy and well completions. Results obtained show three (3) images of the object well from inclination of single edge water and bottom water boundaries. Horizontal well productivity increases for slimmer wellbores and shorter wells, for a given well completion. Results further revealed that, locating the well farther away from the constant pressure boundaries leads to longer oil production than wells located closer to the boundaries. The time of influence of external reservoir boundaries increases with farther well location from the boundaries. Rapid oil production is achieved with stimulated wellbore and large anisotropy reservoirs than damaged wellbores and low anisotropy reservoirs. It is therefore concluded that. for optimum oil MADAKI and ADEWOLE/BJPS, 2(2), December, pg. 47-59 (2025) 48 production from a horizontal well subject to single edge and bottom water drives is possible with slimmer well radius, short and stimulated wellbores and well location as far from the constant pressure boundaries as practicable.