Rafael Nadal began his Madrid Open farewell with a crushing straight-set win over American teenager Darwin Blanch.
The five-time Madrid champion, who has indicated he plans to retire after the 2024 season, took just 63 minutes to complete a 6-1 6-0 victory against his 16-year-old opponent.
Nadal, 37, said this week he will only play at the French Open next month if he feels "capable enough to compete".
He will play Australian Alex de Minaur, who beat him in the second round of the Barcelona Open last week, in the next round in Madrid.
Spain's 22-time major winner was making his return in Barcelona following a three-month injury absence, having feared he may not be able to play again on the professional tour.
The French Open, where Nadal is a record 14-time champion, starts on 26 May.
"Playing here has always been a huge pleasure and the support is difficult to describe in words," Nadal told Sky Sports in Madrid on Thursday.
"I just enjoyed the fact I was able to go out there one more time, and victory gives me the chance to go out there again in two days.
"It's emotional. I am a passionate person but I'm also a stable personality, so I'm enjoying it but also focusing on what I need to be and seeing how far I can go in terms of pushing my physical performance."
In the women's draw, world number one Iga Swiatek beat China's Wang Xiyu 6-1 6-4 to reach the third round.
American third seed Coco Gauff recorded a resounding 6-0 6-0 victory over Dutch player Arantxa Rus, while Greek fifth seed Maria Sakkari beat Croatia's Donna Vekic 6-3 6-2.
But four-time major winner Naomi Osaka is out following a 6-2 4-6 7-5 loss to Russian 15th seed Liudmila Samsonova.