Melbourne: Serena Williams won her eighth and most improbable Grand Slam title, overwhelming top-seeded Maria Sharapova 6-1, 6-2 in the Australian Open final on Saturday. Williams became only the second unseeded woman to win the Australian title in the Open era, coming into the tournament ranked No 81 after spending most of 2006 on the sidelines with a knee injury. It was her first title in 15 tournaments since winning the 2005 Australian Open. It was the most dominating win in a completed championship match at Melbourne Park since Steffi Graf beat Arantxa Sanchez-Vicario 6-0, 6-2 in 1994. She hit a backhand winner to finish it off, threw her racket in the air and dropped onto her back on the court. The 25-year-old American got up and skipped over to the side of the court, swapping high-fives with people in the stands and her mom, Oracene Price. She jogged back onto court with her arms up in triumph. Aggressive play Williams started aggressively and never relented. She held to open and then won 12 straight points after Sharapova had a game point in the next to jump to a 4-0 lead. She saved a break point in the fifth game before Sharapova held at love to make it 5-1. Williams served out, taking the first in 26 minutes on her second set point when Sharapova sent a backhand service return wide. She broke Sharapova's serve and resolved again to open the second set, then had consecutive double-faults to give the 19-year-old Russian a break point chance in the next game. In a manner typical of her determined performance on Saturday, she fired an ace to save the break point and held on back-to-back errors by Sharapova. She led 4-0 before Sharapova held again, avoiding the most lopsided women's final ever at the Australian Open. Serving for the match, she fired two aces to earn triple match point, then finished it off with the backhand in 1 hour, three minutes. Remarkable comeback It was a remarkable comeback for Williams, who had not won a title in 15 tournaments she contested since winning here two years ago. Williams missed nine tournaments immediately after losing in the third round at the Australian Open last year and played only 16 matches in 2006, when she slumped as low as No 140 in the rankings. Despite only having three matches at a low-key Australian warm-up tournament in Hobart, she had enough condition to advance over five seeded players. Her win over No 5 Nadia Petrova in the third round was her first win over a top 10 player since her title here in 2005. Sharapova came into the match on a 13-match winning streak in Grand Slams, having won the US Open last September. After winning her first-round match in three sets over Camille Pin of France, Sharapova had not dropped a set in five rounds before the final.