The £27 million signing impressed alongside the Englishman against Leverkusen, and his new team-mate is confident he will make a big impact at Old Trafford this season
Fellaini, signed for £27 million from Everton on transfer deadline day, impressed on his first start against Bayer Leverkusen in midweek and may feature in Sunday's Manchester derby.
Carrick is already impressed by the big Belgian, and believes he has all the tools to be a real asset to United.
"We now have other options with Felly," he told reporters.
"He brings something different to the squad, which is why the manager bought him, and he has done well in the time he’s been here. Against Leverkusen he was brilliant.
"Now, it’s the big one against City and it’s in these types of games that you want as many forceful players as possible in the side.
"With Tom Cleverley and Anderson also in there, it’s tough for the manager to pick his midfield."