WTA Moments is a video series highlighting key historic milestones at the tour's biggest events. In this installment, WTA Moments: Madrid looks at Dinara Safina's momentous 2009 clay season, when she tallied the biggest title of her career at the Mutua Madrid Open.

Dinara Safina's 2009 clay season was one for the record books. The Russian ascended to No.1 after the Miami Open that season, and consolidated her top spot with a historic run through the clay, which included the biggest title of her career at the Mutua Madrid Open.

The Russian remains the only woman to make the final of the four biggest European clay events in a single season. Playing her first tournament as a World No.1, Safina advanced to the final of the Porsche Tennis Grand Prix before running off 16 consecutive wins with back-to-back title runs at the Internazionali BNL d'Italia and the Madrid Open, before making her second straight Roland Garros final.

WTA Moments: Dinara Safina's title to retirement in Madrid

Having avenged her Stuttgart final loss to Svetlana Kuznetsova in the final in Rome, Safina lost just one set en route to the title in Madrid a week later, defeating an 18-year-old Caroline Wozniacki 6-2, 6-4 to win her second WTA title in eight days. 

"Since I became No.1, I'm playing better and better," Safina said after the final. "I was feeling very comfortable from the start of the match and I was trying to be as aggressive as I could. But even in the key moments I was very strong.''

Safina's 2009 Clay Season: 20-2

d. Errani, 6-0, 6-1
d. Hantuchova, 6-4, 6-2
d. Radwanska, 6-4, 6-2
d. Pennetta, 3-6, 7-5, 6-0
l. Kuznetsova, 6-4, 6-3

d. Razzano, 7-6, 6-1
d. Zheng, 5-7, 6-1, 7-6
d. Martinez Sanchez, 4-6, 6-3, 6-0
d. V. Williams, 6-3, 7-6, 6-4
d. Kuznetsova, 6-3, 6-2

2009 Mutua Madrid Open champions Dinara Safina and Roger Federer.

Photo by Getty Images

d. Li, 6-3, 7-6
d. Safarova, 6-0, 4-6, 6-3
d. A. Bondarenko, 6-4, 6-3
d. Schnyder, 6-4, 6-2
d. Wozniacki, 6-2, 6-4

SLIDESHOW: 2009 Madrid Memories - Safina's Dominance, Mauresmo's Swansong

Roland Garros
d. Keothavong, 6-0, 6-0
d. Diatchenko, 6-1, 6-1
d. Pavlyuchenkova, 6-2, 6-0
d. Rezai, 6-1, 6-0
d. Azarenka, 1-6, 6-4, 6-2
d. Cibulkova, 6-3, 6-3
l. Kuznetsova, 6-4, 6-2

Dinara Safina compiled a 20-2 record over the 2009 European Clay Court season.

Photo by Getty Images

In a season that saw her make two major finals at the Australian Open and Roland Garros, make 8 finals, and capture the last three titles of her career, Madrid remained the highlight for the heavy-hitting Russian. Having trained in Valencia, Spain as a youngster, winning in the Spanish capital was just as meaningful as winning in Moscow.

"The whole 2009, especially the clay court season, was a very special moment for me," Safina said. "Coming to Madrid, being No.1 in the world, and playing almost in front of my home crowd - because I grew up in Spain - there will always be a Spanish side in my heart."

Dinara Safina poses with WTA CEO Stacey Allaster and Manolo Santana at the 2014 Mutua Madrid Open.

Photo by Getty Images

After enjoying the best season of her career in 2009, Safina's career succumbed to injury. She would play the final match of her career in Madrid in 2011, losing in three sets to Julia Goerges. When it came time three years later to officially hang up her racquet and say goodbye, Safina found her closure in Madrid once again. 

"Again, it's Spain," Safina said. "I think that country gave me so much so there was no other country that I could think to say goodbye.

"There was no other place than Madrid."