The announcement comes three days after Spanish coach Francis Roig said he would be stepping down from his role on Nadal's team after 18 years to take on new projects.
"I would like to inform you about the addition of Gustavo Marcaccio to the technical team," Nadal wrote on Twitter.
"Gustavo has been working at the Rafa Nadal Academy since April 2021, and I understand he is a good addition to the team. I'm sure he will help us a lot to continue on our path."
Marcaccio, who was 284th in the ATP rankings in 2004 and coached former Top 10 tennis player Juan Monaco (38), joins Carlos Moya and Marc Lopez as Nadal's coaches.
Nadal, who has won a record 22 Grand Slam titles, will look to successfully defend his Australian Open title at the first Grand Slam of the year in January after an injury-plagued 2022.
