The Belgian midfielder has now overtaken Nikica Jelavic as Everton's top goal scorer with five goals this season and he has been instrumental in their strong start to the campaign.
Jagielka, whose long ball set up Fellaini's second goal, said: "Felli had an OK first half, but in the second he was as good as he has been. He was near enough unplayable.
"Obviously the two goals he got were fantastic. He nearly got another but the keeper made a good save.
"As much as Felli is a big lad, he can play as well. He took his goals well and he took the ball down on his chest and brought other players into play in the 90 minutes."
Steve Sidwell scored a late equaliser for Fulham and Jagielka added: "I think we had enough chances to score another one and possibly kill the game off and maybe then they don't come at us for the last five minutes.
"But it's never over until the ref blows his whistle, so unfortunately again we've dropped two points in the dying minutes."
The England defender was also quick to defend Everton's style of football following criticism from Steven Gerrard after last week's Merseyside derby, saying: "I'm sure for Felli's goal people will have a laugh and a joke but we put a lot of passes together and had a lot of possession.
"People can say what they want, but we need to play it long sometimes. We've got footballers that can play and people who can hold the ball and be physical as well."