Fulham have pinpointed Heerenveen wingers Luciano Narsingh and Oussama Assaidi as two of their summer targets.
Heerenveen gave their consent for both players to travel to England and have a tour of the club's training facilities and Craven Cottage on Monday.
No deal has been struck yet but Mino Raiola, the players' agent, has begun negotiations with the Londoners over personal terms.
"We have given Mino Raiola and the players the space to talk," Heerenveen technical director Johan Hansma told De Telegraaf.
"Narsingh and Assaidi had to have a good feeling with a club. It doesn't make any sense if we reach an agreement with a club and the players won't want to go there. To succeed in a transfer there are three sides needed."
With Clint Dempsey attracting interest from a host of clubs, including Arsenal and Liverpool, Martin Jol is readying a list of possible replacements. Narsingh, who has been included in Netherlands' preliminary 36-man Euro 2012 squad, and Morocco international Assaidi both have one year left to run on their current deals.
Meanwhile, reports in Holland suggest Fulham are lining up a bid for FC Twente star Nacer Chadli - although Twente chairman Joop Munsterman says he has not given permission to the player's agent Daniel Evrard to hold talks with any club.
Munsterman told Voetbal International: "I have become a little bit nervous of Evrard. He always drops a couple of names of clubs, but they never contact us. We aren't talking with any club right now."