So often John Terry has been a decisive factor in a Chelsea trophy triumph.
On Saturday afternoon against Crystal Palace he did the complete opposite, scoring the own-goal that would decide the contest and open up the title race even further.
Joel Ward's cross from the left was met by the jumping Joe Ledley and John Terry with Petr Cech also coming out to meet the ball, the cross took a flick off Terry's head and flew into the empty net.
The Chelsea captain looked devastated after the goal, dropping to his knees with his head in his hands.
Palace performed fantastically well to keep Chelsea in check for the rest of the game through a combination of hard work, last ditch defending and Julian Speroni heroics, and could have had a second after hitting the post through Jason Puncheon.
As it turned out, what looked like a standard away win for the Blues turned into a nightmare, and gave both Manchester City and Liverpool the chance to go above them by the end of the weekend.
Maybe Jose Mourinho was right all along, maybe Manchester City have been favourites all along.