Key found guilty of serious dissent
Key was caught low at midwicket and lingered on the outfield when replays suggested the ball hadn't carried. When the umpires didn't use a replay Key hurled his bat over the boundary.
A statement said: "The panel was particularly concerned that the incident took place during a high profile televised match but took into account Key's unreserved apologies both to the umpires and to the panel."
At the time Key said: "Am I expecting the worst over my dissent? I would imagine I'm going to cop it a little bit but it's one of those things. I wasn't sure [about the dismissal] and then I got given out and, as I was walking off, the players in the dug-out by the boundary who had a monitor said the ball had bounced."
The ECB disciplinary panel of Judge Edward Slinger, Tim O'Gorman and Simon Schanschieff upheld the original ruling on Monday and also ordered Key to pay £400 costs.