The 35-year-old played the full 90 minutes at the Maracana stadium, despite having only begun training with his new teammates on Monday.
Playing in a free-roaming forward role, the former Barcelona star was involved in most of the home team's best scoring chances.
He started the move that led to Fluminense's 77th minute goal when his long pass was flicked on by Wellington Paulista, before Marcos Junior rounded the goalkeeper and fired into an empty net.
Gremio were reduced to 10 men just after halftime when Wallace was shown a second yellow card for a bad foul on Junior.
Ronaldinho praised his teammates and admitted he was surprised to play the entire game.
Aerial photo taken on May 18, 2017 shows historic buildings on the Gulangyu island, southeast China's Fujian Province. Gulangyu island, famous for its varied architecture and multicultural history http://www.jordan6goldenharvest.com/air-jordan-6-release-2017.html , was included on the UNESCO World Heritage list Saturday. The 41st session of the World Heritage Committee on Saturday decided to put China's Gulangyu historic international settlement on the prestigious World Heritage List as a cultural site. So far, China has 52 sites inscribed to the List. (XinhuaJiang Kehong)