The 32-year-old Russian has not played a competitive match since pulling out of the St Petersburg Open in January and underwent surgery on her right shoulder a few weeks later.
She returns to action next week at the Mallorca Open grasscourt event as she prepares for Wimbledon, the tournament that launched her to fame and fortune 15 years when she claimed the title as a teenager.
Sharapova was already training on grass in the sunshine Balearic isle while Nadal was winning his record-extending 12th French Open last weekend, having battled back from knee injuries.
"He is the ultimate fighter and an amazing example of what you can achieve if you have the will and the passion for what you do," Sharapova said on Sunday.
"I've always admired the way he has fought through all the injuries he's had and he's the greatest example of that.
"The sport is so physical, especially the way he plays, but brings an optimistic perspective on his work that he can come back and be a champion. He is extremely motivated."
Five-time Grand Slam champion Sharapova, ranked 86th in the world, says she is pain free and happy to be back on court, although admits the real test will be in matches.
"The shoulder is doing well, I took my time in order to come back to my first event and feel that I have a really good chance at it," Sharapova told Reuters.
"With every match it will be a good test, but I need to get it out into the battlefield to test it.
"You can heal all you want but when you get back to your sport it's a different ball game."
Sharapova admits few people will "give her a shot" at challenging for the Wimbledon title, but believes she has a chance of making an impact if her shoulder holds up.
Most of all, however, she is excited to return with her passion for the sport intact after so many injury setbacks and also missing 15 months because of a doping ban.
"I still have many expectations on myself even though I think I also have many opportunities to do other things," said Sharapova.
"But this sport is very unique and special and I enjoy trying to be better every day."
She said she hopes the decision to undergo surgery will allow her to start enjoying the sport again.
"Before it was about pain management, I wasn't really enjoying playing because after every match I was thinking about what I needed to do to help my shoulder," she said.
"There were some great matches at the start of the year but once I played that first match in St Petersburg I knew that I needed a clear mind."
Asked why she selected Mallorca for her return, she looked up to the blue skies.
"It's a great place to train," she said. "The conditions here are maybe better than the rain delays you may have in England, maybe playing a couple of matches in a day."
Sharapova is scheduled to play her first match on Tuesday.
(Reporting by Martyn Herman, editing by Pritha Sarkar)
