Spaniard Nadal, a 22-time Grand Slam singles champion, has been plagued by injuries in recent years.
After withdrawing from last year's French Open, he said he intended to retire after the 2024 season, but on his return in Brisbane he suggested he may continue if he is fit.
Tuesday's match against Italy's 21-year-old Flavio Cobolli in Barcelona will be his first on clay since he won the title a record 12 times and won the 2022 French Open final. It will be a match.
His return this week has raised hopes that he will compete at Roland Garros next month, where he has won 14 major titles.
“It means a lot to me to play once again at Barcelona, where we have had great success and have so many unforgettable memories,” he said.
“So I'm just trying to enjoy every moment and I'm excited to be on the court again in a professional tournament, especially here at home.
“I haven't been able to spend many days on tour the past two years, so I want to enjoy every day I get to play with players at a professional level. It means a lot to me.”
Elsewhere in the draw UK Dan Evans lost to 22-year-old American Brandon Nakashima 7-6 (7-2), 6-2.
But the British came in second place. jack draperRanked three places above Evans, he defeated Czech world No. 119 Vit Kopriva in the first round of the Bayern International in Munich.
