Thiago Alcantara could be set for an extended period on the sidelines after the Bayern Munich star suffered a thigh injury on Wednesday.
The centre midfielder was forced off the field on the 44th minute in his team's 2-1 away win over Anderlecht in the Champions League with what appeared to be a muscle problem.
Bayern took to their official site after the match to reveal that Thiago would be absent for the immediate future, and head coach Jupp Heynckes admitted he was unsure over the timescale regarding the 26-year-old's recovery period.
He stated: "He [Thiago] most probably has a serious muscle injury in his thigh.”
The veteran boss had better news on Bayern forward Arjen Robben, however, after the 33-year-old Dutch international was substituted around the 48-minute mark due to his own injury issue.
Heynckes added: “I don’t think it’s as bad. He has a slight muscle discomfort.”
Thiago's 2017/18 season has been blighted by a number of niggling injuries as he looked to build on a highly impressive campaign last time around.
The Spain international has suffered from abdominal, knee and back problems throughout the first three months of this term, and had only returned to the starting lineup in Belgium after he sat out the weekend win over FC Augsburg with a slight knee issue.
The defensive midfielder has featured 15 times for Bayern in 17/18, and has bagged three goals despite his position on the field.
Robben, meanwhile, has had a season with very little in the way of injuries - a massive relief to the former Chelsea star after the past few campaigns of continuous injury woes.
The winger has only missed two matches so far this season due to a calf strain and the flu, and will hope that this latest setback isn't yet another starting point in another battle to remain fully fit for the German champions.