Portugal will be without star playmaker Bernardo Silva for their World Cup qualifier with the Republic of Ireland.
The Manchester City player sustained a muscle injury during Saturday's Manchester derby win at Old Trafford, from which he's failed to recover in time.
Silva had missed training on Tuesday, and was again missing as Portugal completed their preparations on Wednesday morning ahead of their flight to Dublin.
However, head coach Fernando Santos hopes to have the 27-year old available for Sunday's Group A showdown with Serbia in Lisbon.
Santos said Silva will remain in Portugal to work with a physiotherapist, and avail of facilities not open to them in Dublin.
Meanwhile, the Portugal boss says he has no concerns over the six players walking a disciplinary tightrope on Thursday night.
Joao Cancelo, Ruben Dias, Jose Fonte, Renato Sanches, Joao Palhinha and Diogo Jota all risk missing their top-of-the-table battle in Lisbon, if they pick up a booking against Stephen Kenny's side.
While Thursday's result is almost immaterial to Portugal's ambitions, Santos insists no foot will be taken off the pedal at the Aviva.
"It's not decisive, but it's very important," said Santos, "We have to play to our standard."
Santos added, "The most important game is this one. We cannot ease off.
"I trust all players. More than the yellow cards and being out of the next game, you have to think about what it means to be on the field.
"As Danilo correctly said, the players will give everything.
"We know it will be a tough game against a strong team. It will be very excited by the public and it never leaves the game. They're a team that knows how to play. That needs to be clarified."
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