Complex sentence: Initially, the CEO was Akshaya Bhargava, who was formerly in Citibank, where he established Citibank captive BPO in 1991, which later became e-Serve International (acquired by TCS in 2008).
Split into simpler sentences: Initially, the CEO was Akshaya Bhargava, who was formerly at Citibank. While at the Bank, he established Citibank first captive BPO, which later became e-Serve International (acquired by TCS in 2008).