Veteran pairing Julien Benneteau and Nicolas Mahut booked France’s place in another Davis Cup final.
They won the doubles to seal the champions’ 3-0 victory over Spain in their World Group semi-final on Saturday.
Spain's experienced duo, 32-year-old Marcel Granollers and 36-year-old Feliciano Lopez were clearly upset after their loss.
Meanwhile, the doubles team of Mike Bryan and Ryan Harrison kept the United States’ hopes alive with a marathon win over host Croatia.
Ranked fourth, Ivan Dodig and Mate Pavic put up a good fight in a match that lasted nearly five hours.