Kevin De Bruyne was missing as Manchester City trained in front of media ahead of Tuesday's Champions League clash with Dinamo Zagreb.
No explanation was given for the Belgium playmaker's absence at the City Football Academy, although it will increase speculation he suffered an injury in Saturday's hard-fought Premier League win at Everton.
The 28-year-old was substituted after 80 minutes of the 3-1 win at Goodison Park but did not look in obvious discomfort as he left the field.
Manager Pep Guardiola also gave little indication that there were any fresh injuries in his squad as he held his pre-match press conference early on Monday.
Asked about injuries, Guardiola said: "Yesterday, everybody was fit. Before the Champions League games everybody is fit. I don't know why but if they have problems they don't tell me."
De Bruyne has been in fine form this season after missing large chunks of the last campaign with knee and muscular injuries.
City host Dinamo in their second match of this season's Champions League having opened in Group C with a 3-0 win over Shakhtar Donetsk in Ukraine.
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