Brentford are reportedly concerned that Kevin Schade could be set for an extended spell on the sidelines.
Schade was selected in the lineup for Saturday's 3-1 defeat to Everton, but he was unable to take his place in the side after sustaining an injury in the warm-up.
The forward injured his left hip during a shooting drill, and was subsequently replaced in the starting XI by Keane Lewis-Potter.
Brentford boss Thomas Frank told reporters after the contest that he was unsure of the extent of Schade's injury issue.
According to the Evening Standard, there are now fears that the 22-year-old could be out of action for a significant period.
The Germany international is expected to undergo a second scan today to establish the full extent of the hip injury.
Schade has featured regularly for Frank's side this season after converting his loan move from Freiburg into a permanent transfer over the summer.
The £20m signing made four starts and two substitute appearances in Brentford's opening six competitive games, before he was forced to miss Saturday's defeat.
Schade also found the net in a 1-1 home draw with Crystal Palace last month to register his first Premier League goal.
In addition to Schade's potential absence, Frank is already having to contend without a number of key players.
Full-back Rico Henry is set to miss the rest of the season after sustaining an anterior cruciate ligament injury against Newcastle United earlier this month.
Ivan Toney, who has been Brentford's top scorer for the last three seasons, is currently serving an eight-month ban for breaching the Football Association's gambling rules.
Josh Dasilva and Shandon Baptiste are long-term absentees, while Mikkel Damsgaard is currently struggling with an injury issue.
There are also concerns that defender Ben Mee could be set to miss the next four weeks after missing the clash with Everton due to a knock.
Despite having to contend with a number of absentees, Frank will hope that his side can bounce back from consecutive defeats when they face Arsenal in the third round of the EFL Cup on Wednesday.
