Roca has become United’s third signing of the summer, joining the Whites from Bayern Munich for a fee in the region of £10m.
The 25-year-old has signed a four-year deal at Leeds and says he will combine tough tackling with passing skills in the Whites midfield.
“My favourite position is a midfielder,” said Roca to LUTV, asked what sort of player he was.
“I like to play with the ball, to be strong in defence and always helping the team.
“The fans can expect me to give my everything.
“I am a player who loves playing with the ball, but I am hard as well in defensive duels.”
He added: “I have to know my new team mates, my colleagues, but I hope Leeds is a team that wants to go in the best position that we can.
“We will do our best, not only for ourselves but for our fans as well.”
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