MELBOURNE, Australia -- Perhaps it's the sugar rush provided by her new line of gummy candy. Perhaps it's the mojo of finally dipping her toe into social media and gaining 76,000 followers in her first week on Twitter, although she's been sparing in her observations so far.
Or perhaps she's simply eyeing a second set of majors after collecting one of each.
Maria Sharapova is surgically carving up the Australian Open draw and looks even more dominant than she did five years ago in that resolute march to the title. She didn't drop a set in 2008 against a more stacked draw, but she's not playing down to lesser opponents here. Through four matches here, the second-seeded Sharapova has let only five games slip through her strings.
"It's really about keeping your focus ... no matter what the score is, no matter if you're up,'' said Sharapova, whose 6-1, 6-0 win over Belgium's Kirsten Flipkens propelled her into a quarterfinal against fellow Russian and 19th seed Ekaterina Makarova. "You know, I didn't start the match really great. I was facing a different type of opponent today and I was making a few more mistakes than I would have liked in the beginning.
"All of a sudden, especially in women's tennis, things can change really quickly.''
At the moment, they seem unlikely to change much until next weekend when, based on form and with all due respect to world No. 1 Victoria Azarenka, most observers would bank on a Sharapova-Serena Williams final.
Williams has owned Sharapova in the eight years since Sharapova pulled off her stunning upset for the Wimbledon championship, and decimated her 6-0, 6-1 in their last meeting on the same turf in the Olympic gold-medal match last summer.
Returning to the present, the 25-year-old Sharapova is not easily derailed when she's got this kind of momentum. Still, her third-round match against Venus Williams was an occasion that required more psychic energy than usual that early in a major. It probably was a competitive blessing to draw a fourth-round opponent unaccustomed to the big stage.
The 43rd-ranked Flipkens, mentored by Belgian icon Kim Clijsters, had never progressed this far in a Grand Slam event. She has resuscitated her career and climbed back from outside the WTA's top 250 after a scary incident last year when doctors diagnosed blood clots in her legs after a lengthy airplane trip. Flipkens now takes blood thinners and wears compression stockings for long flights.
She said Sharapova crushed her faint hopes early in the match.
"I didn't have many chances,'' Flipkens said. "I didn't play badly, but when she hits like this, she's playing on another planet.''
Flipkens' best chance was to defend gamely, try to utilize her slice to lure Sharapova to net and hope Sharapova would falter, but the Belgian couldn't take advantage of the one stretch in which Sharapova allowed herself to be seriously pressed.
In the fourth game of the first set, on serve, Sharapova faced three break points and committed three double faults during an extended game before cracking an ace to follow the last misfire. That seemed to cure her and she reverted to the methodical form of the first three rounds.
"I really started making her play a little bit more,'' Sharapova said. "Started really getting under the ball and being aggressive and just had a little bit more energy, which really helped me and I carried that throughout the match.''
The 24-year-old Makarova, who knocked Serena Williams out of the tournament in straight sets in the fourth round last year before her own run was ended by Sharapova, will try to construct another Australian Open upset. She radiated contentment with her progress in this edition and described herself as "interested and excited" about the matchup, which may be the only logical place to start.
"She won a lot of matches easily because she is playing so aggressive, staying into the court,'' Makarova said of Sharapova. "I have some plan against her. We played a lot of times so we know each other. I think we'll be a good match and I try to show my best tennis.''
Sharapova, who has swept all four of her previous meetings with Makarova, said she has felt differently en route to each one of her Grand Slam championships -- and, indeed, the snapshots look like four different people.
There was her youthful upset of Williams at Wimbledon in 2004; her jumping-up-and-down, trophy-jarring, late-night victory at the 2006 U.S. Open; the controlled emotion of her straightforward 2008 win here; and the gratitude she expressed after the most unlikely victory of all, last year on the clay of Roland Garros, where many discounted her prospects of ever winning.
In between, she's felt the edge of a few scalpels herself, both literal and figurative. Her commercial trajectory shot skyward and stayed there, but the rest of her career has been a Ferris wheel ride.
Sharapova has survived various repairs to her body, matured from being a sometimes aloof adolescent to a more accessible, self-deprecating personality, adjusted her service motion and survived her own maddening stretches of inconsistency. There might be no player in the game who presents such an interesting combination of power and vulnerability.
At the moment, she's on the ascent.