Vikings left guard Brandon Fusco practiced Friday for the second straight day but had not cleared the NFL's concussion protocol before the team listed him as questionable on the week's final injury report.
Jeremiah Sirles, for whom Minnesota traded with San Diego to add depth when center John Sullivan was sidelined after back surgery, is in line to replace Fusco against the Chargers on Sunday at TCF Bank Stadium.
"It just kind of happens the way it happens," said Sirles, who was acquired Sept. 5 for a sixth-round pick. "You never foresee anything happening like this.