Muamba could barely believe his eyes when he witnessed his former boss lose it following the Gunners' FA Cup fourth-round exit at the Reebok two years ago.
Wenger took his anger out on the visitors' dressing-room door after Stelios had headed a late winner in January 2006. Muamba, on the Arsenal bench that night, said: "Arsene Wenger doesn't lose it that often but he did that day.
"I'd just signed my professional contract and my reward was a place on the bench.
"The tie was goalless going into the last 10 minutes but then Stelios scored with a header. It wasn't a pleasant sight afterwards. All managers have got different sides to them.
"But I had never seen that side to him before. I thought 'wow' because I'd never seen him like this."