Michu, 28, passed a medical with Rafael Benitez's side on Thursday and will link up with the Serie A outfit ahead of their pre-season preparations.

"Swansea City can confirm that Michu has joined Napoli on a season-long loan with an agreed option to buy," a statement on the club's website announced.

"The 28-year-old completed a medical earlier today and will now link up with Rafa Benitez's side ahead of the new campaign."

Michu was a big hit after arriving at the Liberty Stadium in 2012 from Rayo Vallecano in a �2 million ($3.4m, 2.5m euros) deal.

After netting twice on his Premier League debut in a 5-0 win over Queen's Park Rangers, the Spaniard went on to score 22 goals in all competitions as the Swans finished ninth in the Premier League and won the League Cup.

But he struggled to recapture that impressive form last term as injuries took their toll.

Napoli finished third in Serie A last season, qualifying for the Champions League, and lifted the Coppa Italia for the fifth time in the club's history.