Who is No. 1 this year? The rankings say Serena Williams. But the titles say Victoria Azarenka, who has won Brisbane and the difficult back-to-back Indian Wells and Miami.

Serena has zero titles this year in three tournaments.

While Williams withdrew from Madrid citing the “flu,” Azarenka on Monday improved her 2016 win-loss record to 26-1, beating Alize Cornet 6-3, 6-2 at the Mutua Madrid Open.

“I had two completely different type …

Roger Federer pulled out of the Madrid Open today due to a back injury. Federer, who also withdrew from Miami, was a late entry into the event last week.

Federer arrived in Madrid last week in perfect health, but injured his back during practice on Saturday. And instead of risking further injury, he wanted to play it safe.

“Sorry to the tournament for coming and leaving without playing,” Federer said. “I arrived …

In the midst of doping allegations, Rafael Nadal says he believes the sport of tennis is clean.

“I believe in my sport,” Nadal said Sunday in Madrid. “That’s the most important thing. I believe that my rivals are clean. I believe the sport is clean and I believe in our anti-doping program, no, and it’s an independent one.”

Nadal also reiterated his position that the doping process and the results should be …

Rafael Nadal has once again found his footing on the slippery clay surface. The former No. 1 turned around a disappointing start to 2016 by winning consecutive titles last month in Monte Carlo and Barcelona, defeating Andy Murray, Gael Monfils, Stan Wawrinka and Kei Nishikori during this 10-match win streak.

“I’ve been competing against the players and won matches against some of the best players of the world and competed pretty …

Top-seeded Aggie Radwanska’s weaknesses were exposed on her least-favorite surface Sunday when the scrambling Dominika Cibulkova ousted the Pole on the red clay at the Mutua Madrid Open 6-4, 6-7(3), 6-3 in the opening round.

She will next meet Caroline Garcia, who advanced when Johanna Konta retired with an upper respiratory illness.

Other upsets on the day were Czech Barbora Strycova ousting No. 2 Angie Kerber 6-4, 6-2; Montenegro’s Danka Kovinic topping …

In one of the best matches played this season, German veteran Philipp Kohlschreiber edged Dominic Thiem 7-6(7), 4-6, 7-6(4) to win his third Munich Open title.

“Unbelievable. Great story the whole week. Great performance. Huge final,” the 32-year Kohlschreiber said following the 2-hour, 31-minute victory. “I’m very happy and pleased with my performance.”

Kohlschreiber picked up his seventh career title, first of 2016. And it’s redemption after losing to Andy Murray …

Former Top 10 Nicolas Almagro came from a set down to beat countryman Pablo Carreno Busta 6-7(6), 7-6(5), 6-3 to win the Estoril title on Sunday.

The victory was Almagro’s first since 2012 Nice and 13th of his career. The 30-year-old beat Nick Kyrgios in the semifinals yesterday. He’s also the first Spaniard to win Estoril since Albert Montañes in 2010.

Ranked No. 71, Almagro is expected to move up into Top …

Up a set and a 5-2 Grigor Dimitrov was in full control of the Istanbul final against big underdog Deigo Schwartzman, headed toward his fifth career ATP title. But funnier things have happened, and a short while later it was Schwartzman holding up the trophy after winning 11 of the last 12 games for a 6-7(5), 7-6(4), 6-0.

“I started cramping at 5-2 in the second set,” said Dimitrov. “It was …

Former French Open semifinalist Timea Bacsinszky collected her first title of 2016 and first of clay crushing qualifier Marina Erakovic 6-2, 6-1 in the Rabat, Morocco final Saturday.

“Well, it’s a great feeling, and my first win on clay,” she said after the match. “It was an awesome week for me; it was tough at the beginning but I leveled up my game and I’m really happy about this win. I …

After missing an extended period of time dealing with a bacterial infection at the end of 2015/start of 2016, Lucie Safarova is finally back to her winning ways. The 29-year-old won her first title in over a year beating Sam Stosur 3-6, 6-1, 6-4 to claim her home Prague event.

“I had quite a few tough matches here so I feel pretty tired,” said Safarova who beat Karolina Pliskova in …

Dominic Theim knocked down wunderkind Alexander Zverev 4-6, 6-2, 6-3 to advance to the Munich final where he’ll face another German in Philipp Kohlschreiber.

“It’s unbelievable how he plays at 19 years old,” Thiem said. “I lost the first set and then I changed a little bit… more slice, more drop shots, and I think this was one of the key points to win it.”

Thiem will seek his third title of …

Looking at the past champions in Madrid, the tournament has been dominated by the Big 4 since its switch to clay in 2009. The quartet of Novak Djokovic, Andy Murray, Roger Federer and home hero Rafael Nadal have accounted for the last seven titles there (10 of the last 11 if you include the indoor event), and there’s little reason to think that trend won’t continue next week in Spain.

The …

The young guns continue to make their presence felt on the ATP Tour. Today in Estoril, 21-year-old Nick Kyrgios knocked out 19-year-old Borna Coric 6-4, 6-4 in a highly-anticipated Next Generation matchup.

Kyrgios now collides with Nicolas Almagro. Another under-24 Pablo Carreno Busta stunned top seed Gilles Simon to reach the semifinals. He’ll meet Benoit Paire.

“I’m not going to think about it too much,” Kyrgios said of playing Almagro. “I know …

The Madrid Open confirmed Roger Federer will play in the event which begins on Sunday.

“Federer is one of the best players in history and Madrid is a special place for him,” tournament director Manolo Santana said. “We are delighted to have him back in the Caja Mágica. In addition, he is one of the fans’ favourites because of everything he has achieved in his career. We will be welcoming …

Flu has forced Serena Williams out of the Madrid Open on Friday. Serena made the semifinals last year when she lost to Petra Kvitova, and twice won the event.

“Unfortunately, I have to withdraw from Madrid because I’ve been battling the flu and I’m not at 100%. I look forward to returning soon,” Serena said.

The 34-year-old hasn’t won a title since Cincinnati last summer and she’s just 2-2 …