Rudi Garcia's men currently top Serie A with seven wins from seven, and the Italy international believes they will be fired up for success this season after recent disappointment
The Giallorossi have won all seven of their opening games in this season's Scudetto, with a convincing 3-0 away win at Inter on Saturday maintaining their two-point lead over both the champions and Rafa Benitez's side.
Marchisio believes Rudi Garcia has had a major impact on the capital club's revival this term and believes that, without European competition as a distraction, they will be fully focused on returning to the top of Italian football in 2013-14.
"In the long run, I fear Roma more than Napoli," the Italy international told reporters. "They haven't changed much, they have lots of quality, and you can see the hand of the coach that's raising them up.
"The Giallorossi have no European commitments and want to rebuild after a couple of disappointing seasons. Maybe they are hungrier than us. This will help their concentration and will to win.
"Of course, we must see if Roma can sustain this rhythm."
Juventus secured a hard-fought win over AC Milan last weekend to maintain the pressure on Roma, and Marchisio was pleased to see his side recover their clinical edge against Massimiliano Allegri's men following a disappointing Champions League draw with Galatasaray.
"On Sunday, we were more cynical than in previous games," added the 27-year-old. "It was important to get the three points as Roma and Napoli are not losing points."