Azarenka has already won titles in Brisbane and Memphis this year
By Piers Newbery
Victoria Azarenka claimed the biggest win of her career as she defeated five-time champion and world number one Serena Williams in the Miami final.
The 19-year-old Belarusian won the Sony Ericsson Open 6-3 6-1 as Williams, playing with heavy strapping on her left leg, struggled physically.
Azarenka, the world number 10, won four straight games to take the first set.
And the teenager sealed her first win over Williams in three meetings as the American faded badly in the second.
"It was a little difficult moving to the left and a little bit to the right. A little forward was also difficult," a smiling Williams said afterwards.
"I don't like to not play. I gave the effort that I could give today. That's all I could give."
I'm not one to make excuses, I give Victoria all the credit today
The victorious Azarenka said: "You could see the leg tape right away, but I wasn't really paying attention too much because I had to play my game and I had to keep her moving as much as I could."
Azarenka has made steady progress over the last couple of years to her current high of number 10 in the world but has yet to get past the fourth round of a Grand Slam - making this the biggest match of her career to date.
The final was played in the heat of the Florida afternoon and brought memories of the pair's last meeting.
Azarenka was controlling their Australian Open fourth-round clash in January before retiring through illness in the scorching Melbourne heat, and the teenager called for an ice pack on an early changeover this time.
The Belarusian began nervously, while Williams appeared keen to keep the points as short as possible as she coped with her injury worries, making for a scrappy start to the match.
After swapping breaks in games three and four, Azarenka moved ahead for the second time at 4-3 when Williams went long with a forehand.
The 27-year-old American kept battling and saved three set points in game nine before finally sending a backhand into the net to fall a set behind.
Williams' problems came to a head in game four of the second set as she could no longer push up on the serve, double-faulting twice to hand over the break.
Azarenka did what she had to and stayed focused as she closed in on a breakthrough victory, coping with the occasional blockbuster from Williams and maintaining her solid hitting from the baseline.
It was in a subdued atmosphere that the Belarusian served for the match and finally she faced a crisis, firing a backhand past the incoming Williams to save one break point and surviving another with a good first serve.
Her first ace of the match was then followed by her seventh double-fault but Azarenka overcame the attack of nerves, converting her third match point when Williams put a backhand long.
"I was so nervous, I couldn't believe I had the match point," Azarenka admitted afterwards. "I really wanted another chance to play her because in Australia we unfortunately couldn't finish. This is really big; I would say it was the biggest moment in my career."
Williams said: "Even when I was down match point I thought I could still win; I didn't really know how, but I thought it was a possibility.
"I think she has really, really improved. I actually look forward to playing her again so I can do better."
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