STUTTGART, Germany -- Looking relieved, Maria Sharapova went through her familiar routine of waving to the crowd and blowing kisses after winning her first match on her return from a 15-month doping ban on Wednesday.

The five-time Grand Slam champion and former No. 1 beat Roberta Vinci 7-5, 6-3 in the opening round of the Porsche Grand Prix.

"It was the best feeling in the world," Sharapova said about stepping on court again for a professional match. "I have been waiting for this a long time."

Sharapova had earlier been given a lukewarm welcome by the 4,500 spectators, receiving a polite applause and some whistling when she entered the sold-out arena.

The Russian had not been afraid of the reception that awaited her, despite the fact that she entered the event on a much-debated wildcard.

"It's not something you focus on because you spent so many months training and preparing and getting ready that you have to be in your mind when you're walking out on court," she said.

Sharapova was not looking back in anger at her suspension, saying: "I am not an individual that's angry. I let things go pretty quickly. Sharapova added that she had "a pretty normal life" and "grew as a person" while being away from the circuit, until getting back to training in January.

"I was studying, I was working, I was working on my business, I formed friendships that I did never have the time for to form," she said.

Wednesday's match was the Russian's first since losing to Serena Williams in the quarterfinals of the 2016 Australian Open, and her first match on clay in nearly two years.

Against the 36th-ranked Italian, Sharapova had a shaky start, conceding seven of the first eight points and dropping the opening two games within five minutes.

She finally took her fifth chance in the third game to break Vinci's serve.

Apart from producing a string of unforced errors, Sharapova also showed flashes of her old self - with several outstanding returns and cross-court winners, mostly followed by her trademark fist pump.

When Vinci held serve to go 5-4 up, the Italian had already won more games than in her two previous matches, both two-set defeats, against Sharapova.

The Russian, however, broke again and converted her second set point with a forehand winner to take the opener.

Sharapova took control of the second set after an early break and held off three break points in her following service game.

She dropped only two points on serve in the rest of the match and closed out the win on Vinci's serve to go 13-1 for the Stuttgart tournament after winning it three times on four appearences.

"It's good for tennis that she has come back," Vinci said after the match. "She played good, she played aggressive, very solid, good service. She deserved to win."

Vinci added "it was tough to stay focused before this match. Of course lots of pressure. If you see Facebook and Instagram, always 'Sharapova-Vinci, Sharapova-Vince, first match.' It was tough for me to stay focused but I tried to enjoy the moment."

Last year, Sharapova tested positive for the banned substance meldonium. She had her initial two-year ban reduced to 15 months by the Court of Arbitration for Sport, which ruled that the Russian bore "less than significant fault" in the case and that she could not "be considered to be an intentional doper."

Sharapova had been taking meldonium for many years, but overlooked an announcement by the World Anti-Doping Agency that it added the drug to its banned list on Jan. 1, 2016.

As a result of the suspension, Sharapova lost her ranking. But the three-time winner from 2012-14 was given direct entrance to the main draw of the Stuttgart event. Organizers in Madrid and Rome followed the example and handed her a wild card for their events in May as well.

Several players, including Vinci, have criticized the invitation for a player who has been caught doping.

Sharapova said "it's not my job" to think about other people's comments.

"Words and quotes and articles is not what matters in life, I have learned that very well over the past year," she said. "Articles, they go away, that is not life. What matters is what happens on the court."

Sharapova added that "I'm not getting a wild card to receive a trophy. I still have to win the matches and that's my job."

Earlier Wednesday, Sharapova completed a one-hour training session on an empty centre court. Because her suspension ended only at midnight, she had not been allowed to use official tournament facilities before, forcing her to visit a local tennis club in Stuttgart for training since last weekend.

Sharapova next plays fellow Russian Ekaterina Makarova, who upset the seventh-seeded Agnieszka Radwanska Tuesday.

In other first-round play, Kristina Mladenovic beat Australian Open semifinalist Mirjana Lucic-Baroni 6-4, 6-2 to set up a second-round match against the top-seeded defending champion, Angelique Kerber. Sixth-seeded Johanna Konta defeated Naomi Osaka 7-6 (5), 3-6, 6-1, while Carla Suarez-Navarro and Elena Vesnina also advance.

Simona Halep became the first player to reach the quarterfinals after beating Barbora Strycova 6-2, 6-3.