The 25-year-old departed in the second half after taking a knock, but Villa swiftly allayed concerns over the severity of the problem.
A message posted on the club’s official Twitter page read: “Gabby Agbonlahor injury not as bad as first feared. Out for two weeks.”
England striker Darren Bent played no part against Chicago due to a slight thigh strain.
Lambert’s side, who beat the Philadelphia Union on Wednesday, now head to Portland for a game on Tuesday.
Agbonlahor injured in Villa win