The wide man left Elland Road on a temporary basis, but not before speaking to the Whites’ record signing – who used to ply his trade for the Bats.
"The first thing I did was talk to Rodrigo Moreno," said Costa.
"He told me many good things both about the club and the city and it was an easy decision. I am happy to be here. Guedes was my partner at Benfica. I've known him for many years. I spoke with him before coming and he told me that the Club had all the conditions for me to continue evolving.
"Valencia CF is a very big team. I'm very excited and I want to start working. I want to do my best for the team.
The other conversation Costa had before agreeing to the move was with José Bordalás, Valencia's May-appointed head coach. His style of football at previous club Getafe was known to be quite direct, in possession, with the ball played up to a front two to play off flick-ons, or out wide for wingers to compete against full-backs. His Getafe side produced a high volume of accurate crosses to create chances, and without the ball employed an aggressive press. Costa, after two years working under Marcelo Bielsa, should be well accustomed to Bordalás' defensive demands.
"The coach's game is attractive, it suits my style," he said.
"I talked a bit with the coach before coming, I watched some videos of the team and I saw that they play very attractive football, very fast and I think it suits my style of play. I am a fast player who likes one-on-ones. I play for the team. I like to score goals but also assist my teammates."
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