Alisson Becker is an injury doubt for Liverpool's clash with Bournemouth, manager Arne Slot said on Friday.
The Brazil international has started each of Liverpool's four Premier League games this season, keeping three cleansheets and also featured in the Merseyside club's 3-1 win over AC Milan in the Champions League on Tuesday.
However, Slot clarified that Alisson's injury predates the midweek game at the San Siro.
"Alisson is still a doubt if he can train today. We have to wait and see," Slot said at a news conference on Friday.
"He has a slight issue with one of his muscles. We wonder if this game tomorrow is coming too early or not," he added.
"He didn't do it in the Milan game, he felt it before then he felt it more and more. Now we have to see if he's ready for the weekend."
In the build-up to their Champions League opener, Alisson had been critical of the increased workload footballers face, saying "nobody asks the players what they think about adding more games."
When Slot, who joined Liverpool from Feyenoord in the summer, was asked about the contrast between the football calendars in Netherlands and England, he said: "Until now I haven't seen anything different but Premier League has four extra games and the League Cup. From the start to now we've played just as many games as at Feyenoord -- that's not an issue to me.
"But [the] main difference with Premier League to Europe is we have to play at Christmas and New Year. The quality of the league, of [Nottingham] Forest and Bournemouth, is much much higher than if you play in Eredivisie against a team not challenging for the top six.
"We are thinking about what's to come, we are aware of the fact it's a long season. We need a lot of players so they also need once in a while playing time and we take that into account when making a line-up."
One player who has struggled for minutes at Liverpool this season is Darwin Núñez, who has yet to start or score for the club this season. However, Slot was encouraged by his showing off the bench against Milan and said he expects the goals to come for the Uruguay international.
"He needs the same as all the others, work really hard and the goals will come. that's what he did against Milan, he came in for the team and then as a result of that attackers have goals or assists. It happened with Cody [Gakpo] so if you play for a team like Livepool you'll get them," he said.
"For me it's the work you do without the ball. He will get his chance in the near future, we play a lot of games, he is fitter and fitter and understand day by day what we want from him. But he's in competition with Diogo [Jota] who has done well."