Williams will take on Pironkova on Monday after sweeping aside the mostly hapless Martinez Sanchez 6-0 6-2 on Court One.
Williams edged past veteran Kimiko Date-Krumm in her second-round match, but showed no signs of weakness yesterday, losing just 13 points in the first set before continuing to overpower her Spanish opponent with a powerful and aggressive performance in the second.
Pironkova produced one of the shocks of the tournament last year when she knocked out five-time champion Williams in the quarter-finals.
The American looked out of sorts against Pironkova that day, wasting break points and double-faulting on her way to defeat.
She admits she was well below par then, and has vowed not to make the same mistakes again when the pair meet on Monday.
“Last year I didn’t play that well, unfortunately. I don’t feel I competed well. Regardless of how I play, I know I’ll be competing this time,” said Williams.
Twelve months ago Williams lost 6-2 6-3, and now she believes she can turn the tables.
“This is the fourth round. Now I’m ready to bring my best game and my best competition,” she said.
“Last year I think I just got unhappy with how I was playing and I let that affect my game. This year I won’t let that happen.
“I let a few games get away, and instead of coming back, I let it all get to me. You can’t do that, especially in a Wimbledon quarter-final. I won’t let anything get to me this time.”
Williams may have missed the majority of 2011 with a hip injury, but she showed no signs of discomfort today, combining power and precision in a win that was wrapped up in an hour and one minute.
The seven-time grand slam champion knows that Pironkova will go into next week’s clash full of confidence though, having knocked out No 2 seed Vera Zvonareva 6-2 6-3 this afternoon.
“It looks like she’s playing pretty well,” Williams said.
“She moves well and she looks like she can mix up her shots really well. To take out the second seed is never an easy task.”
“But I feel like I’m moving very well at the moment, which is exciting for me, especially after all my injuries,” Williams added.
“It seems I do move quickly to the net on grass.”