Chelsea boss Frank Lampard insists there's no great emotions facing West Ham today.
Lampard was signed by Chelsea from West Ham.
But he insists: "I would not say it is a bitter-sweet experience for me in any way.
"It is just a game for us to try to win against very difficult opponents. A London derby adds spice to it which the players have to be aware of because that can change the temperature of the game.
"I am not concerned about the emotions from my point of view. I came through the academy there a long, long time ago, I have been at Chelsea a long time as a player and now a manager so the focus is completely on us.
"I expect West Ham to bring passion and effort. They are in a difficult place because of their recent run, and sometimes that can bring out the best in players.
"You look at people in their team like Mark Noble and Declan Rice, players that care for the club, and they want to react to a manager who is a top manager so I am expecting a reaction from them. We know they have individual quality in forward areas so I am taking the game nowhere near lightly. It is a tough match."
