he former world number one and Argentine partner Juan Monaco overpowered second-seeded Czechs Frantisek Cermak and Lukas Dlouhy 6-3 6-2 in 65 minutes at the Pacific coastal city of Vina del Mar.
Spanish left-hander Nadal had been out with a knee problem since losing to Czech Lukas Rosol in the second round at Wimbledon in June.
"It's a good feeling to be back. We'll see how the knee reacts," Nadal told a news conference. "The moment and the surfaces were the right ones and playing for the first time in this country was a great opportunity.
"Playing doubles is less aggressive, so we'll see how things go tomorrow in singles," he added after he and Monaco had taken advantage of four of their seven chances to break the Czechs' service.
The 26-year-old's planned return at the end of last year was delayed due to illness but he will compete on his favourite clay surface at three Latin American events this month.
On Wednesday, Nadal plays a second-round singles match against Argentine qualifier Federico Delbonis.
After the Chile tournament he will compete at the Brazil Open in Sao Paulo next week and the Mexico Open in Acapulco from February 25.
- Sports & Recreation
- Juan Monaco
- Lukas Dlouhy
- Lukas Rosol