Levein felt referee Bobby Madden and his assistant cost his side when there was no offside flag raised as Alfredo Morelos netted in Rangers’ 2-1 Tynecastle win.
The Jambos boss also claimed the Colombian should have been sent off for a series of fouls.
Gerrard said: “Craig’s entitled to his opinion, like I am when I speak about Hearts or Aberdeen or whoever it may be.
“I saw the interview when he said they were playing against 13 men. The only mistake I saw in the interview was that it was 14, because our fans were superb on the day.
“So it was probably 14 they played against.”