CARLSBAD - Australia's Sam Stosur won her first title in nearly two years when she upended world number two Victoria Azarenka 6-3 6-2 to win the Carlsbad Open on Sunday.

In registering her first victory over the Belarussian in nine attempts, Stosur played an opportunistic and clutch contest, fighting off 11 of 12 break points while breaking Azarenka in every game she had the chance to do so.

"She had a lot of opportunities and all of them except for one I hit a really good first serve and she didn't get a ball into play," Stosur told reporters.

"That's something I have to be very happy with, to step up the line under pressure and hit the serves where and how I wanted to time and time again.

"I know what it feels like not to break serve when you have the opportunities, it can get pretty frustrating."

The fifth seeded Stosur had come close to defeating Azarenka in their last two meetings at the 2012 US Open and 2013 Rome, but she hadn't been able to contend with her foe's vicious returning and superior movement.

But the Azarenka that faced Stosur in Carlsbad was just coming off knee and hip injuries she suffered at Wimbledon, and appeared to be a little slow to the ball and inaccurate off the ground.

Stosur broke Azarenka in her first service game to go up 2-0, but then was broken straight back when the two times Australian Open champion ripped a backhand down the line.

But Azarenka handed the break right back by committing three straight errors to go down 3-1, and after Stosur was able to hold in the next game to 4-1 by fighting off five break points with a series of hard serves, she gained control of the contest.

Stosur fought off another break point with a big body serve to go ahead 5-2, and then won the first set when Azarenka committed two more errors.

Stosur was able to fight off another five break points to open the second set, bombing aces on two of the break points, which left Azarenka muttering to herself.

Azarenka's level continued to drop and Stosur broke her to 4-2 when she dumped a backhand into the net.

On her first match point, the Australian watched Azarenka careen an easy backhand well wide.

"I didn't take my chances, but she was really serving well today," said Azarenka, who finished the contest with only 11 winners and 32 unforced errors.

"I was trying to do the same thing that wasn't working. That wasn't very smart for me to do. But I have to give her credit, she played great."

The 29-year-old Stosur said that the title was exactly what she needed heading toward the U.S. Open, which she won two years ago.

"This is a huge boost for me," said Stosur, who ripped 20 winners and forced Azarenka into 18 errors.

"I haven't had great results all year, so to be able to bounce back from last week's first round loss (at Stanford) and play better and better each day and come away with this is a good boost going into the last Slam of the year."