Crystal Palace have agreed a deal to sign Porto defender Bruno Martins Indi, Sky sources understand.

Sky Sports News HQ understands Martins Indi will head to Selhurst Park subject to agreeing personal terms and passing a medical.

Martins Indi spent last season on loan at Stoke City and had been expected to return to the Potteries on a permanent deal.

He was nearly ever present for Mark Hughes' side, playing in 35 Premier League games and scoring a single goal.

But their option to sign him expired on July 1 and the Netherlands international now seems set to join fellow Dutchman Frank de Boer, who is now in charge at Selhurst Park.

Martins Indi has one year left on his contract at Porto.