Having worked extensively with Fellaini at close quarters, Round is certain the 25-year-old's skills and abilities will complement those of his new team-mates.
"He will add some real physical presence to us in midfield, some strength, and he scores goals," Round told MUTV.
"He's a player that will get regular double figures, and he is maybe a player that we didn't really have in the middle of that midfield.
"Maybe we needed that bit of presence and authority that can sit in the middle of the pitch and dominate a game from that perspective. It gives a nice blend and balance to mix the midfield up."
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