The selection includes strikers Michy Batshuayi, Eden Hazard, Romelu Lukaku and Dries Mertens; midfielders Yannick Carrasco, Nacer Chadli, Kevin De Bruyne, Mousa Dembélé, Leander Dendoncker, Marouane Fellaini, Thorgan Hazard, Adnan Januzaj, Youri Tielemans and Axel Witsel; defenders Toby Alderweireld, Dedryck Boyata, Laurent Ciman (reserve), Vincent Kompany, Thomas Meunier, Thomas Vermaelen and Jan Vertonghen. Thibaut Courtois, Koen Casteels and Simon Mignolet are the three Belgian goalies for the World Cup.
Laurent Ciman is being held in reserve in case Vincent Kompany fails to return to health.
The line-up is bad news for Matz Sels, Christian Kabasele, Jordan Lukaku and Christian Benteke, who have fallen off the list.
Quizzed about Kompany, who dropped out against Portugal due to injury, Martinez explained that Belgium would take advantage of the FIFA rule allowing it to replace an injured player up to 24 hours before the kick-off against Panama on 17 June: "We wish to give 'Vinnie' as much time as possible to take care of his injury" he told reporters. "His leadership is essential for us. During the entire preparation he has shown himself to be a leader. He works hard and played a fantastic match against Portugal. That wasn't just any international match."