Andrey Rublev battled through a suspected virus and an anaesthetised foot to beat Felix Auger-Aliassime 4-6, 7-5, 7-5 to claim the Madrid Open title on Sunday, but revealed that he will now have to return to hospital to make a full recovery.
The 26-year-old Russian, who has struggled with health issues throughout the tournament, recovered from the illness and an opening set wobble to clinch his second Masters 1000 title in just under three hours.
"I'm still sick and tomorrow I think I'll go back to the hospital for a full check-up to know exactly what's going on," Rublev told a news conference.
"I've been sick for eight or nine days now, it's not normal, I'm not really getting better, which is strange because usually I get sick for two or three days at the most and maybe a fever, but nothing special. This is the first time in my life that I feel this bad."
The seventh seed said that he needed an anaesthetic to play the final.
"They put an anaesthetic in the finger on my foot because somehow it got inflamed and started to get bigger and the pressure started to be on the bone and I can't even put my shoe.
"The feeling was similar to when you broke it, so they put an anaesthetic so I me to don't feel it and at least I could play without thinking."
Rublev, who came into the Madrid tournament in poor form having lost his previous four matches on the tour, eliminated second seed and home favourite Carlos Alcaraz and also beat American Taylor Fritz to reach the final.
"I think it is normal to have ups and downs, but my focus now is to keep working and trying to improve. I think I showed a great level of tennis from the first match and in the end I was able to win the title.
"Now I think the most important thing is to try and recover and be ready for Rome," he added.