Sent packing from the Australian Open after her straight set third round defeat against the big-hitting Venus Williams, Sania Mirza on Saturday admitted she counts among the worst servers in the game.

Once again, Sania's serve proved the proverbial Achilles' heel as she went down 6-7 (0/7) 4-6 to the eight seeded former Wimbledon champion after putting up a spirited fight.

"Obviously, I'm a little disappointed because I felt I had the first set and should have closed it out at 5-4," the 31st seed said after her match against Venus which lasted a little over one and a half hours.

"I think we always knew that she's one of the best servers in the game, and I'm really not. I mean, I'm very critical about my game. I think I'm one of the worst servers in the game," Sania said.

The 21-year-old fought hard in the match and felt despite the loss, she could take away a lot of confidence for future matches.

"I take a lot of positives out of it. I mean, she's supposed to be one of the biggest hitters of the game, and I was outhitting her. And I think that's a very good thing for me, for my confidence," she said.