Miami  - Teenager Victoria Azarenka reinforced this week's move into the Top 10 as she reached her third final of the season with a marathon 6-3, 2-6, 7-5 defeat of former champion Svetlana Kuznetsova at the Miami Masters on Thursday.

The 19-year-old, Arizona-based Azarenka spent nearly three hours and needed four match points to finally book her spot. She awaits the result of the clash later between sisters Serena and Venus Williams, who between them hold eight titles at their home event.

"It feels great that all the work I've been doing is paying off," Azarenka said. "I was just trying to play every point from the beginning to the end.

"The second set didn't go so well for me, but I was still hanging in there."

Azarenka also re-wrote a painful episode in her recent history after holding a match point, but losing to 2006 champion Kuznetsova in the 2008 round of 32 at Crandon Park.

On a steaming hot afternoon, the youngster from Belarus was unable to serve out victory with a 5-4 lead in the final set as Kuznetsova saved a match point from an error and then profited as the nervous Azarenka double-faulted for 5-all.

But the Russian's serve let her down in the next game, with the Belarusian youngster breaking for 6-5.

Azarenka finally clinched the win a game later after Kuznetsova salvaged another two match points but fired a backhand into the net to end the encounter.

Kuznetsova, working now without a coach and trying to find her way, said that she exceeded her modest expectations.

"I've not been winning a lot, coming here I felt lost on the court. I didn't know what I was doing, so I was trying some new stuff and then some old stuff and I was a little bit messed up.

"If you had told me coming to the tournament that I'd make the final, I would doubt. But I was fighting all I could in the third set."

Azarenka triumphed in a hard slog with 26 winners and 42 unforced errors, breaking on six of her dozen chances.

"It was really, really tough, but I was preparing myself for a long match," said Azarenka. "The last points and the last games was really, really tough.

"I'm just so happy that I found energy and that fighting moment. I had to fight, you know, no matter what. That was kind of (an) adrenaline in the last games. I didn't have so much energy."

Kuznetsova had won all three of the pair's previous meetings, losing only one set in the process.

But the experienced Russian who won the 2004 US Open was unable to nose over the line against the talented number 10, winner of events in Brisbane and Memphis this season.

The Williams pair will be playing for Serena's number 1 ranking with a loss to her sister Venus automatically shifting Russian Dinara Safina into the top spot from Monday. (dpa)