Paulo Bento's men know they cannot afford any more slip-ups if they want to top their pool and avoid having to qualify for the World Cup through the playoff round.
Paulo Bento's side is one point behind Russia, but the pool leaders will be expected to take maximum points from their final two matches, against Luxembourg and Azerbaijan.
Victory over Israel in Lisbon on Friday would at least ensure Portugal finishes no lower than second, so it could still progress through to the playoffs. Captain Cristiano Ronaldo has called on his side to focus on its own job by defeating Israel before collecting a further three points when it faces Luxembourg.
"I am confident in the victory," Ronaldo said. "They are two games we have to win, we are the favorites, and we will get on the field and give the best to ensure the six points. We just have to win both games and see what Russia does."
Ronaldo does not want to consider the possibility of Portugal -- a World Cup semifinalist in 2006 -- failing to qualify for Brazil 2014.
"All players play in big clubs and know the responsibility of playing in the national team. Missing two games and not winning is not worth thinking about," Ronaldo said. "We have the better team and we need to show that on the field; we have a great chance to win the game."
Portugal has not lost a competitive match since October 2012 and hosts Israel, which sits five points back in third. Israel’s last victory came back in March and it was beaten by Russia last time out to put a major dent in its hopes of pulling a stunner and getting out of the group into at least the playoff round.
The previous group meeting between Portugal and Israel saw the former come from 3-1 down to snatch a draw through Fabio Coentrao’s late equalizer. Coentrao is suspended on this occasion, along with Helder Postiga, while Bruno Alves, Joao Pereira, Miguel Lopes and Raul Meireles are all missing through injury.
Meireles' absence, due to a problem with his right thigh, was confirmed on Wednesday, with Custodio called up as a replacement.
Israel coach Eli Guttmann also has a squad blighted by injuries and has chosen to recall Barak Yitzhaki and Eden Ben Basat. Dudu Aouate retains his place, but there is no room for ex-captain Yossi Benayoun.