Gillingham striker Adam Birchall will discover the full extent of his knee injury on Friday after undergoing a scan.
The 26-year-old, who arrived from Dover this summer, had to be stretchered off during Tuesday's 3-0 friendly win over Welling.
"There's no point trying to put a timeframe on the injury at this stage but we expect to get the scan results through [on Friday]", boss Andy Hessenthaler told the club's official website. "Then we will have a clearer idea of the situation
"It's a tough one for Adam because he's desperate to impress and make his mark again at league level.
"Obviously we are keeping everything crossed for him and hopefully we'll see him back in a blue shirt again very soon."