Carragher had questioned Eze's ability to make an impact with the Gunners after his August move from Crystal Palace.
But after last night's performance, Carragher said on Sky Sports: "I must be honest. In the summer when Arsenal signed him, and I had my Liverpool hat on, and I looked at the signings Arsenal made... they signed (Victor) Gyokeres. It felt like a lot of them were to strengthen the squad, really.
"Where Arsenal had problems the year before was when (Bukayo) Saka was out, so they brought (Noni) Madueke. (Martin) Odegaard was out, so they got Eze. One of the centre-backs was missing, so they got a couple of centre-backs.
"It was only really Gyokeres who I felt was going to go in the team. And if I'm being honest, I think if (Kai) Havertz was 100 per cent fit, Havertz would probably be the centre forward in this team.
"When Eze came in, I thought, 'Okay, maybe it's not a gamechanger'. We've seen some of his highlights this season, there's been a few great goals in there. And then he goes and scores a hat-trick.
"So, apologies. I certainly undervalued the importance that signing was, because he looks like he could make the real difference for Arsenal and go on and win the title."