(CNN) Her serve was on. She ripped returns for winners, celebrating with a clenched pumped fist.
And when she won, she was visibly emotional as she waved to the crowd.
Maria Sharapova is back -- and she returned as soon as she possibly could.
On Wednesday, her first day eligible to return to the WTA Tour after serving a 15-month doping ban, the 30-year-old Russian defeated Italian Roberta Vinci 7-5, 6-3 in the first round of the Porsche Grand Prix in Stuttgart, Germany. Sharapova finished with 11 aces and had 39 winners. She broke Vinci, a former US Open finalist, at love to close out the match.
"I've been waiting for this moment for a long time," Sharapova said on court after the win.
Sharapova, a former world No. 1 and five-time Grand Slam champion, wasn't allowed at the venue until the morning of the match. She trained off site while her suspension was still in effect. The tournament started on Monday.
"Yes, you're rusty and you're trying to get the rhythm again," Sharapova said. "It's my first match in a while, but this is what I've done for so long, and when you're in the moment, you try to block everything out, and you compete. And I'm a competitor by nature, even when things are not working. That's what I do."
Sharapova has won the Porsche Grand Prix three times, from 2012-2014. She will face Russia's Ekaterina Makarova in the second round Thursday.
Vinci falls to 0-3 against Sharapova.
In March 2016, Sharapova announced that she had tested positive for meldonium. She said she failed to realize the heart drug she had taken for more than a decade for various health issues had been added to the prohibited list of the World Anti-Doping Agency from January 1, 2016.
She initially was given a two-year ban by the International Tennis Federation, but it was reduced on appeal to 15 months.
Wednesday's match was Sharapova's first since she lost to Serena Williams in the Australian Open quarterfinals on January 25, 2016.
Sharapova's return isn't without controversy.
Sharapova was given a wild card for the Porsche Grand Prix main draw by tournament organizers. In tennis, wild cards are awarded to players either in the main draw or the qualifying draw (pre-tournament qualification). Because Sharapova currently is not ranked, she needed a wild card in order to play.
Porsche is one of Sharapova's sponsors.
Sharapova also has received wild cards for tournaments in Rome and Madrid. Should she accumulate enough points from those tournaments, she could qualify for the main draw of the French Open, the next major on the tennis calendar. Tournament organizers for Roland Garros will announce a decision on Sharapova on Facebook on May 16.
"There is no reason to make an exception for Maria Sharapova," French Tennis Federation President Bernard Giudicelli said Wednesday.
Despite her absence from the tour, Sharapova earned $21.9 million in 2016, according to Forbes. Only Williams ($28.9 million) earned more.