Victoria Azarenka (L) of Belarus and Serena Williams of the US pose with their trophies after their women's singles finals match at the US Open tennis tournament in New York, Sept 9, 2012 file photo. [Photo/Agencies]

NEW YORK -- World number one Serena Williams of the United States booked a rematch against world number two Victoria Azarenka of Belarus after winning Friday's semi-final against Li Na of China 6-0, 6-3 in the US Open tennis tournament.

Li Na missed the chance to have a second Grand Slam show after reaching the final of the Australian Open earlier this season. The 31-year-old Chinese had reached at least quarter-final in three of the four Grand Slams in 2013.

"I have a more stable season this year," said Li about her 2013 WTA journey. "No matter if I win a match or lose one, I always want to improve."

"I hope next season I can do better."

The first set was totally under the dominance of Williams. The winner of 16 Grand Slam titles converted all three break points to beat Li 6-0, another clean sweep after she overwhelmed Spaniard Suarez Navarron 6-0, 6-0 in the quarter-final.

"I got a little nervous, but I was able to close it out, finally," said Williams.

Li tried hard to recover from the second set. She held her own serve in the second game, winning her first game in the match, and then broke Williams' service game to get 2-1 lead. However, Li failed to extend the lead to 3-1 when she was 40-0 in the fourth game. Williams managed to accomplish another break to level the score to 2-2.

The world number one was difficult to play against when she got her rhythm. She took down three straight games to make a 5-2 lead.

The Chinese top female player saved as many as six match points in the eighth game of the second set. However, Williams served out the match 6-3 in the ninth.

"In the end, finally I can play tennis," said Li.

Last four placing was the best record for Li in her US Open participation history.

"Today it doesn't matter who is the opponent. Problem is myself, because today I cannot face to the problem," said Li.

"Even today I was playing against maybe the ranking 100, still the same problem, you know."

Williams managed to win her six US Open matches with 12 sets, in which she only lost 16 games. She had a 24-game winning streak starting from the second set in her victory over Sloane Stephens until the 1-0 second set lead over Li.

She was trying to become the first female single player to win US Open title without dropping a set since 2008, in which Williams herself accomplished the difficult task.

Williams would face Azarenka, the same opponent in last year's final, to fight for her 17th Grand Slam title on Sunday.

The second seed Azarenka beat unseeded Italian veteran Flavia Penneta 6-4, 6-2.

It was the second straight time for the 24-year-old Belarusian to reach US Open final after the runner-up show last year. It was also her first victory against Pennetta since 2010.

Azarenka broke Pennetta in the very first game, only to see Pennetta break back in the second. Azarenka had a chance to serve out the first set at 5-4. The second seed wasted five set points, but still took the sixth to finish the first set 6-4.

The second set almost went on the same route as the first one. Azarenka accomplished a break again in the first game, and Pennetta broke back. However, Pennetta failed to keep her second service game, allowing Azarenka a 3-1 lead. The winner of 2013 Australian Open won three of the following four games to end the match 6-2.