Rafael Nada defeated Alexandr Dolgopolov 6-3, 7-6 (3) to win the Rio Open 2014 titl.
Nadal looked comfortable in the final and improved his record on clay to 298 wins and 21 losses, the best in the Open Era.
The Spaniard declined to talk about his back, focusing instead on the victory.
"Clearly, it was important for me to get back and win after what happened in the final in Australia," Nadal said.
He said the heat, the court preparation and the quick balls used in the event made it difficult. He has complained about the fast balls all week.