Van Nistelrooy retired as an international after Euro 2008 but this season he rescinded that decision.
"I told him that we followed him intensely and admired his ambition and effort to get to the World Cup," Van Marwijk said in a statement released by the Dutch football federation.
"I think that Ruud (van Nistelrooy) is fit but there was not enough time for him to reach his normal level after a long-term absence due to his knee injury."
Goalkeepers: Maarten Stekelenburg (Ajax Amsterdam), Sander Boschker (Twente Enschede), Michel Vorm (Utrecht)
Defenders: Vurnon Anita (Ajax Amsterdam), Khalid Boulahrouz (VFB Stuttgart), Edson Braafheid (Celtic), Giovanni van Bronckhorst (Feyenoord), John Heitinga (Everton), Joris Mathijsen (Hamburg SV), Andre Ooijer (PSV Eindhoven), Ron Vlaar (Feyenoord), Gregory van der Wiel (Ajax Amsterdam)
Midfielders: Ibrahim Afellay (PSV Eindhoven), Otman Bakkal (PSV Eindhoven), Mark van Bommel (Bayern Munich), Wout Brama (Twente Enschede), Orlando Engelaar (PSV Eindhoven), Nigel de Jong (Manchester City), David Mendes da Silva (AZ Alkmaar), Stijn Schaars (AZ Alkmaar), Wesley Sneijder (Inter Milan), Rafael van der Vaart (Real Madrid), Demy de Zeeuw (Ajax Amsterdam)
Forwards: Ryan Babel (Liverpool), Eljero Elia (Hamburg SV), Klaas Jan Huntelaar (AC Milan), Dirk Kuyt (Liverpool), Jeremain Lens (AZ Alkmaar), Robin van Persie (Arsenal), Arjen Robben (Bayern Munich)
