Diogo Jota has given Liverpool manager Jurgen Klopp an injury headache ahead of Saturday's Premier League trip to Watford.
The 24-year old has left the Portugal camp ahead of Tuesday's World Cup qualifier with Luxembourg.
Jota missed Saturday's friendly with Qatar due to a muscle problem, and Portugal manager Fernando Santos has decided to release the forward back to his club.
"He trained a while ago, increased the intensity today with [physio] Joao Brito, but he didn’t train with us," Santos told the media on Monday.
"The probability [that he will play] will be little. I’ll talk to him, see how he feels.
"If we see that he has any conditions to be on the bench and then come in, that’s fine.
"If we don’t, we won’t take the risk with a player who hasn’t been able to train with us for a long time."
Jota's injury will be a concern for Klopp, having preferred the forward ahead of Roberto Firmino for most of the new season.
He's rewarded the Reds boss by scoring 3 goals in 7 Premier League games.
Jota is also Portugal's top-scorer in World Cup qualifying Group A - ahead of Cristiano Ronaldo - with 4 goals.
Portugal go into Tuesday's games trailing Serbia by a point at the top of the group, but with a game in hand.
Santos told the media on Monday that the meeting with Luxembourg will be a difficult one. Serbia only managed a 1-0 win in the Grand Duchy on Saturday, courtesy of a second-half goal from Dusan Vlahovic.
"From what I saw in the game against Serbia it was very difficult for Serbia," Santos said, "They [Luxembourg] lost but it was unfair.
"Serbia had about five goalscoring opportunities, but those who saw only the summary have the wrong idea."
Santos added, "Luxembourg had most of the ball. They are growing, it's not the selection of 30 years ago... nor of five years ago, we played at that time and I could see it.
"Now we played there 5-months ago and we had difficulties in the game.
"We scored close to half-time, we know that,Luxembourg is always looking to play and want to have the ball.
"Gerson [Rodrigues] and the Young Boys striker [Christopher Pereira] didn't play that day. They should play now and it give them something extra."