Traditional approaches of executing complete system test suite to validate software systems on deploying the upgrades of Commercial Off-The-Shelf (COTS) software components is typically costly and time-consuming, resulting in delay in deploying the upgrades. In this paper, we present a process that examines the test case dependencies at finer granularity level of alteredfunctions in the upgrades of COTS software and recommends a smaller regression test suite. The process captures and analyzes the functional-level runtime interactions among the applications and COTS components to find the impact of the upgrades on the system. The process includes a procedure to identify the altered-functions in a component. We have developed a prototype based on the concepts proposed in the paper and performed a case study on a web-based application to illustrate efficacy of the prototype. The results of the case study show that up to 80% reduction in regression test efforts could be achieved.