Watford midfielder Miguel Layun has joined FC Porto on a season-long loan deal.
Porto also have the option to to by the 27-year-old for a fee of €6 million.
Layun, who can play on the left-hand side of defence or in the midfield, joined Watford from Granada in January and made a total of 17 appearances as the Hornets won promotion to the Premier League.
The Mexico international scored the Vicarage Road outfit’s opening goal of the Premier League season as they drew 2-2 at Everton.
Layun told Porto’s official website: “I feel great, happy to be here and to be part of this great team, that is used to fighting for the biggest goals, due to their greatness.
“I am eager to start training, to be at the same level as my teammates and to fight for a spot in the starting team.”