Didier Drogba kept Chelsea's faint title hopes alive as he scored the only goal of the game against Portsmouth at Fratton Park on Tuesday. The 30-year-old had threatened on numerous occasions throughout the match but he finally found the back of the net 11 minutes from time.Jose Bosingwa whipped in the cross low from the right where the ball was flicked on at the near post for Drogba to meet it…