(CNN) -- Serena Williams is looking forward to the "ultimate challenge" of trying to win the French Open after again proving her dominance over biggest rival Maria Sharapova and defending her Madrid title on Sunday.
The American triumphed 6-1 6-4 to retain her No. 1 ranking and claim the 50th WTA Tour crown of her career, becoming only the 10th player to do so.
The 31-year-old is the only player to have won on three different colors of clay -- and she is confident that the Madrid surface's reversion to red after the blue of 2012 will help her bid to end an 11-year wait for her second grand slam success at Roland Garros.
"This court is definitely different from last year," Williams said. "It definitely plays more like Roland Garros, so I think that's a plus. It's a little slower than it was last year and plays more like a true clay court. So I think it's great preparation. It's a good start in the right direction."
Last year Williams fell at the first hurdle in Paris -- a tournament she won back in 2002 -- before going on to triumph at Wimbledon, the Olympics, the U.S. Open and the season-ending WTA Championships.
"It is the ultimate challenge," Williams said. "Whether I reach it, I don't know. I'm not going to put that pressure on myself.
"I wanted to do it last year and I didn't get it. So this year I'm just looking forward to Rome, and then after that Roland Garros."
Williams has now beaten second-ranked Sharapova in their past 12 meetings, and was in control for most of the match despite trailing 3-1 in the second set.
"I don't know if her start was shaky, but I felt I played well in the first few games -- playing such a great athlete and great tennis player like Maria, you have to come out and play well. I had no choice," she said.
"She definitely started playing better in that second set -- I think she came out with a different game plan. I missed a very crucial point in that first game, but after that I just had to refocus."
Williams is now three wins behind Monica Seles on the WTA list, but a long way behind Martina Navratilova's record 167.
"I don't know how many more I can win. Like I say every day, 'Who knows if I'll ever win another title?' I just want to live in the moment," said Williams, who returned to action in 2011 after a long injury break that caused life-threatening blood clots on her lungs.
"I feel like every moment I play -- I don't know if it's because of what I went through -- I feel like I'm so fortunate to be out there and healthy and to have an opportunity to play a sport and be really good at it.
"Hopefully I can just keep it going."
Sharapova arrived in Rome having retained her Stuttgart title, but the Russian was once again unable to stand up to Williams' power.
"Obviously it's tough losing in the final today, but I think my preparation so far has been decent, winning a title in Stuttgart and getting to the final in this tournament for the first time," the 26-year-old said.
"One more tune-up to go before Roland Garros, and everything seems to be going well."
Rafael Nadal is in fine shape to defend his French Open title after winning a record-extending 23rd Masters level tournament in Madrid on Sunday.
The Spaniard crushed Swiss 15th seed Stanislas Wawrinka 6-2 6-4 in the final to claim his fifth crown since returning from longterm knee problems in February.
The 26-year-old joined Thomas Muster in equal second on the Open Era clay titles list with his 40th success on the surface. They are six behind Guillermo Vilas.
Wawrinka can take some consolation in that he will return to the top-10 rankings for the first time since 2008.
It was Nadal's third title in Madrid, where he has been runner-up twice.