Two of Heerenveen's biggest stars Jeffrey Gouweleeuw and Filip Djuricic have left the club, joining AZ Alkmaar and Benfica respectively.
It was revealed earlier in the year that Serbian international midfielder Djuricic, 21, would be heading to the Estadio Da Luz - but the Portuguese giants have now confirmed his arrival,
Benfica are paying €6million for Djuricic - who has signed a long-term contract, after three-years with Heerenveen.
Centre-half Gouweleeuw, also 21, has penned a five-year contract with AZ.
"It took some time, but I am happy the deal has been worked out now," he said.