The 30-year-old has been a consistent performer in the Manchester United first team under Jose Mourinho despite being something of a controversial figure at Old Trafford.
Fellaini has often come in for criticism for his physical style of play but there is no doubt that he can be effective when needed.
Mourinho seems to value his contribution to the Manchester United team highly, and the Red Devils boss would have been satisfied with his performance at Vicarage Road on Saturday as he notched up an assist in the 2-1 win.
And former Everton man Osman was clearly impressed by what he saw from Fellaini as Manchester United made it back to back wins in the Premier League at the weekend.
Speaking to BBC Radio 5 live, Osman said: “It was down to Fellaini. His position protected Lindelof. He protected him from the physicality.
“He is very good at what he does in both ends of the pitch. He allowed Matic and Pogba to be more involved in the game.”
Manchester United will return to Champions League action on Wednesday night when they take on Young Boys at Old Trafford.
The Red Devils are aiming to be one of the main contenders for the Premier League title this season after they ended up second and without a trophy last term.
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