The Spaniard moved to Stamford Bridge from Unai Emery’s outfit in the summer, and in an ironic turn of fate both teams were drawn in the same Champions League group.
Despite it being good to see former team-mates again, Mata has claimed he is ready to help Chelsea get a victory.
“It is going to be strange for me. I was here for a few years and it’s going to be odd for me to go into a different dressing room,” he stated to Mirror Football.
“It will make it special for me. I know about the atmosphere in the Mestalla when Valencia play in the Champions League. I know how special the game is going to be and I’m very happy to be here.
“But I don’t know if it will be hard for me to play against my former team. We will find out what it feels like.
“I’m focused on helping the team win. Before and afterwards, I will say hello to my friends here, but the focus is on helping Chelsea win the game,” he concluded.
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