I agree that its unlikely Chelsea will sell to Spurs, given their recent transfer history and that Mata could get into most sides in Europe, but stranger things have happened.
Don't get me wrong, I'm not deluding myself into thinking he will be featuring in the NL Derby on Sunday, but I'm hoping that something could be done to see Mata in a Spurs shirt next week. I share the same thoughts as SpursDisciple (above)
We shall see what happens in the coming 4 and a bit days.
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Edit: Looks like the dream is dead.
From BBC Sport:
Tottenham manager Andre Villas-Boas rules out signing Chelsea midfielder Juan Mata. Spurs did enquire about the possibility of signing Mata, but Villas-Boas concedes there is no chance that the Blues will offload one of their players to a rival club.
"First, Chelsea wouldn't sell to Tottenham in any way or form, as they think that we are title contenders," he said. "Mata is a great, great player - player of the season last season - very, very important player for Chelsea.
"They're just not going to strengthen another team that, in their opinion, are rivals for the title."