Denmark international Eriksen joined United on a free transfer in pre-season after playing the second half of the 2021-2022 campaign with Brentford.
It was initially unclear how United would fit Eriksen into the team given the importance of Bruno Fernandes, but Erik ten Hag's inability to land key transfer target Frenkie de Jong seemingly made the decision for him.
Eriksen has generally featured slightly deeper than Fernandes and the pair's collective creativity has been a real asset for United in midfield.
That was particularly plain to see in the impressive 3-1 win over Arsenal, as Eriksen's passes to Fernandes were crucial in the build-up to two of United's goals.
Of the United players to feature for more than 190 minutes in the league this season, no one has averaged more passes (50.4), successful passes ending in the final third (11.2) or passes into the box (5.6) on a per-90-minute basis than Eriksen, highlighting how quickly he has managed to stamp his personality on their style of play.
"I'm not surprised one bit," Carrick said.
"I played against him a lot; I've watched him a lot. I like him a lot. He's a fantastic footballer. He's clever, he's smart.
"It almost doesn't matter what position he plays, he can adapt. He's just a clever, intelligent footballer with great quality.
"I was pleased when we signed him, and he's not surprised me one bit. He's a top player."
Eriksen carried his encouraging United form – which earned him their Player of the Month award for September – with him into the international window, impressing for Denmark over the course of their two games.
He scored a stunning long-range effort in the 2-1 defeat to Croatia before producing a wonderful performance in Monday's (AEST) 2-0 win over France as he remarkably laid on eight chances for team-mates.
To put that into context, Eriksen has only registered more key passes in a single club match twice (nine both occasions) since joining Tottenham from Ajax in 2013.