The other players were named in Spanish media reports as Ernesto Escobedo of the United States, Uzbekistan's Denis Istomin, Bernabe Zapata Miralles of Spain and Serbia's Pedja Krstin. Nadal will be seeded second with Dominic Thiem third.
Some were left in no doubt as to their thoroughness.
The French Open starts next weekend. "I felt that deep in my thoughts!"
He won the title without beating any top 10 ranked players, but avoided any serious controversy after his fourth-round default at the US Open. However, Nadal was quick to shake off any excuses for his straight sets defeat to Diego Schwartzman, who was playing at a spectacularly high level. "I just try to be happy, to take the positives from this tournament and to go there (Paris) smiling".
© APARC Romania's Simona Halep returns the ball to Kazakhstan's Elena Rybakina during the final match of the Dubai Duty Free Tennis Championship in Dubai, United Arab Emirates, Saturday, Feb. 22, 2020.
Playing in his maiden ATP 1000 final, eighth seed Schwartzman raced out of the blocks to convert two break point opportunities for a 3-0 lead as Djokovic's usually clinical backhand offered up some errors.
"It's a completely special year and unpredictable year", said Nadal whose Rome appearance was his first on the tour since February.
The world number one defeated Diego Schwartzman 7-5 6-3 in Monday's final, the same scoreline he had recorded to defeat Casper Ruud in the last four to reach a 10th final at the tournament.
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Aniston and Pitt were one of the biggest celebrity couples of the 1990s and married in 2000 before divorcing in 2005. "I wish I could say [Pitt and Aniston's reunion] was my plan all along", Dane Cook , the read's organizer, joked.
Djokovic, who has won 31 of his 32 matches this year, said he would have to raise his game further to challenge for the title at the French Open, which begins on Sunday.
Victory in Rome came on the day that he notched up his 287th week as world number one, passing Pete Sampras on the all-time list and with just Roger Federer on 310 ahead of him.
Also missing is US Open victor Naomi Osaka, yet to get beyond the third round in the French capital, who is nursing a thigh injury.
"I have two dreams, you know, tomorrow", said the 28-year-old from Buenos Aires.
Conditions in Roland Garros could also have an impact, with the tournament pushed back to autumn because of the coronavirus pandemic.
Meanwhile, Roland Garros will debut its new retractable roof on the showpiece Philippe Chatrier Court.
The only real issue for Djokovic this past week was his behavior again.