The clock showed 55 minutes.
Cesc Fabregas slipped the ball down the left channel, finding Diego Costa isolated against Kyle Walker. Costa took a good touch with his left to stop the ball. Then he took a not so good touch with his right, pushing himself (and the ball) just a bit too far wide and too close to the touchline. He did create some space (Walker was a bit slow and hobbled, carrying a possible injury) and swung a left boot at the ball. Was he crossing? Was he shooting? It's unclear. It doesn't really matter. What matters is that the ball was heading across six-yard box at speed. Any little touch would've been enough to divert it into the net. And sure enough, there was a touch, Kyle Walker's touch. Hugo Lloris practially dove out of the way, helpless. Chelsea were up 2-0 and on our way to winning the League Cup.
Now, a month later, we even have official confirmation on whose goal it was that sealed the deal. Much to my surprise, it's been awarded to Diego Costa!
... Diego Costa was credited with the second goal in our Capital One Cup victory over Spurs at Wembley [...] so he has 20 goals to his name so far this season, 19 in the Premier League.
-source: Chelsea FC
Apparently the process for determining dubious goals in the League Cup goes a little something like this:
Chelsea FC: We say it's Diego Costa's goal!
Capital One Cup: Ok.
Everyone else: Ok.
Diego Costa: [spares life of official statkeeper]
So there you have it. Diego Costa now has 20 goals, officially. Nineteen in the Premier League. One in the League Cup. Somewhere, an abandoned and starving dubious goals panel sobs quietly in a corner.
Fun fact: the last three players to get 20 goals in a season, in all competitions, have all been Spanish: Juan Mata, Fernando Torres, and now, (sort of, in more ways than one) Diego Costa. Hurray!