The Mirror says Vadillo, 18, is seen as one of Spain's best prospects and has been compared to a young Cristiano Ronaldo.
Now, the two north London heavyweights, who meet on Sunday, the day before the summer transfer window closes, are chasing him.
Spain Under-20 starlet Vadillo has a £17million buy-out clause in his contract.
But Arsenal boss Wenger, who has detailed his scouts to watch the player, would hope to get him for less than that fee.
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