George Telegraph shocked East Bengal 3-1 in the Kolkata Premier League at the Yuba Bharati Krirangan on Thursday.
Nigerian striker Shaheed Olawale struck twice, in the 23rd and in the 33rd minutes, while Gour Naskar sealed East Bengal's fate, scoring the third goal in the 38th minute.
Asim Biswas pulled one back for East Bengal in the 40th minute.
In other KPL matches Thursday, Mohammedan Sporting defeated Eastern Railway by a brace at Barasat stadium and Chirag United and Calcutta Port Trust (CPT) played out a goalless draw.