The striker is expected to join Jose Mourinho's side in a £35 million move from Atletico Madrid in the near future after he passed a medical with the Premier League giants on Wednesday.
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"I wish him the best," Mata told reporters.
"He is a forward who is very well suited to English football because of his power and strength. He is the type of player that thrives there, but at the moment he is still an Atletico player."
Mata was then asked about the World Cup and he says he is elated to be part of the Spain squad again heading into another major tournament.
He said: "I'm over the moon and very proud to have been to two Confederations Cups, a World Cup and a European Championship and now I'm getting ready to experience another World Cup.
"I'm proud to be part of the most historic period in our national team's history. I'm raring to contribute and to keep enjoying this moment; here's hoping we keep making history."