Zenit St. Petersburg midfielder Danny and Atletico Madrid right-back Silvio will miss Portugal's Euro 2012 play-off games against Bosnia & Herzegovina.
Danny is currently far from full fitness with a sprained right knee, a problem which saw him miss the club's 1-1 draw with Kuban at weekend, while Silvio is still nursing a pubic bone injury.
Both players had missed Portugal's last two Euro 2012 qualifiers, against Iceland and Denmark, and have been allowed to return to their respective clubs to continue their recovery.
Meanwhile, coach Paulo Bento has called up Malaga winger Eliseu and PAOK midfielder Vieirinha for the crucial play-off encounters.
Eliseu started Portugal's last two matches in the absence of Fabio Coentrao, while Vieirinha has earned his first-ever call-up.
The Euro 2004 runners-up will face Bosnia & Herzegovina in Zenica on November 11 before hosting Safet Susic's men at Lisbon's Estadio da Luz four days later.