PARIS (AP) - On the days when her doctors argued over what was wrong and her right shoulder barked each time she reared back to serve, Maria Sharapova used to ask herself a question.
When is this going to end?
One thing she never questioned was how much she loved tennis.
A three-year comeback that began from the depths of a hard-to-diagnose shoulder injury reached a high point Saturday, when Sharapova walked out of Roland Garros as the French Open champion.
She completed the career Grand Slam with a 6-3, 6-2 victory over Sara Errani and picked up the last piece of that puzzle on the red clay, the surface she once said made her feel like "a cow on ice."
This, she said, plus the No. 1 ranking she picked up this week, are the ultimate rewards for fighting through 10 months of rehab, for setting aside the doubts, for finally finding a plan that worked after so many didn't. For sticking with the sport she's been playing for almost as long as she could walk.
"I love my work. I love playing tennis," Sharapova said. "I've had so many outs and I could have said, `I don't need this. I have money; I have fame; I have victories; I have Grand Slams.' But when your love for something is bigger than all those things, you continue to keep getting up in the morning when it's freezing outside, when you know that it can be the most difficult day, when nothing is working, when you feel like the belief sometimes isn't there from the outside world, and you seem so small."
That, to sum up, is how Sharapova stayed motivated even during the darkest days, when some people were telling her she didn't need surgery and others were telling her she did, and when the truest answers she found were not from doctors or trainers, but from the sharp, stabbing pain she felt every time she reached her shoulder above her head.
"People were saying I had inflammation, which was really frustrating because I knew there was something more to it," she said. "Then after that, it wasn't getting better as soon as everyone thought it would. That was the frustrating thing because it was like, when is this going to end?"
A successful operation to fix the tears in her shoulder finally did do the trick, along with the long days of training and rehab.
She slowly climbed from the depths of the rankings _ from as low as 126the _ to No. 1, which is where she'll be when the new list comes out Monday. It will be her first turn at the top spot since June 2008.
"I remember when I met her when she was 13, she always told me she wanted to be No. 1," Billie Jean King said. "First, she said, `I want to be a star, and I said, `Whoa, what does that mean? Does that mean you want to make lots of money?' `No, no, no,' she said, `I want to be No. 1. That's what a star is.' She was emphatic about being No. 1."
Sharapova became the 10th player to complete the career Grand Slam, putting her in rarified air alongside King, Chris Evert, Martina Navratilova and Serena Williams, to name a few.
Afterward, Sharapova talked about how she felt eight years ago, when she was 17 and she won her first Grand Slam tournament on the grass at Wimbledon.
"I thought when I won Wimbledon at 17, that would be the most treasured moment in my career," she said. "But when I fell down on my knees today, I realized this is extremely special, even more so."
A few days after brushing off the thick, red Roland Garros clay, she'll get ready to head back to the All England Club as a much different person, a much different player. She has rounded out her collection of Grand Slam trophies, but to say she is going to sit back and enjoy it _ well, she loves tennis too much to say that.
"Keep going. Keep improving. That's always my goal, whether I win or lose," she said. "I'll retire the day I wake up and don't believe I can be a better player."
AP Sports Writer Melissa Murphy in New York contributed to this report.