Improved productivity, resource utilization, and efficiency are crucial for the industries working with batch production systems and have attracted growing interest from academia and practice. Five focusing steps approach (FFS) of the Theory of Constraints (TOC) is considered a reliable solution to achieve these ends by effectively elevating the constraint within the system. Although earlier studies highlighted significant advantages of FFS to the manufacturing firms that adopt it, empirical validation from the real-life cases about these benefits is unaddressed in the literature. Most of the studies on TOC concepts are found to have utilized hypothetical cases to demonstrate their applicability. However, this study successfully implemented the simulation-based TOC application in the real-life case of the Indian automobile component manufacturing firms using a resource reallocation strategy to elevate the constraint. A simulation model of the firm under study is created in a discrete event simulation software, ARENA^©. The simulation results show that the TOC implementation resulted in an improved manufacturing performance viz. Throughput and resource utilization. The results also establish that the application of TOC reduces the lead time and shown a positively productive efficiency.