Dembele was key to Spurs' fight-back from 2-0 down to draw 2-2 in the first-leg of their Champions League last 16 tie.
Gerrard could not hold back how impressive Dembele was in his eyes.
"I thought (Mousa) Dembele's performance was magnificent," he began. "I can't remember him putting in a performance like that on that stage. I thought he was terrific all night."