The defending champion, chasing a record-extending 12th title at Roland Garros, powered through the first two sets before being slightly bothered in the third, Reuters reported.
But the second seed from Spain, who looks to become the first player to win a Grand Slam title 12 times, stayed business like when Maden broke back for 4-4 and the contest ended when the world number 114 returned wide.
“He’s a good player, he had won four matches — three in qualifications — going into this match, he had gained confidence,” an always gracious Nadal told a courtside interviewer on Court Suzanne Lenglen, where he has never lost.
His only two defeats in 90 matches here happened on the main Court Philippe Chatrier.
“For me it is an important victory, playing here in Paris, at Roland Garros, is always incredible,” the 32-year-old added.
Nadal will take on Belgian David Goffin, the 27th seed, for a place in the fourth round.