Crystal Palace are looking to improve their back four before the start of the season and Frank de Boer has looked at the Porto star Bruno Martins Indi as an ideal target.
According to The Times, the Eagles have already agreed on a deal with Porto for the Holland international but the player is yet to undergo his medical at Selhurst Park.
As per the report, Palace are willing to pay Porto around £12.5 million for the 25-year-old centre back.
Martins Indi was on loan at Stoke City last season and the Potters had the option of signing him permanently for a fee of £8.