When Serena wakes up, watch out

KEY BISCAYNE, Fla. -- There have been days, particularly in recent years, when being Serena Williams simply hasn't been enough. We refer you to last year's U.S. Open final, when the 13-time Grand Slam singles champion was, shockingly, blown off the court by a muscular Australian named Samantha Stosur.

Serena cracked her racket and completely lost her composure after being called for a rare hindrance by the chair umpire. For Stosur, it was her first major victory and only the third title of her career.

Early Monday afternoon at the Sony Ericsson Open, the two were locked in a fourth-round rematch with Stosur up a break, at 4-2 in the opening set. That was when Serena -- admittedly, not a morning person -- suddenly awakened in ferocious fashion. She stroked a monster forehand that even the powerful Stosur could not absorb, fired a 121-mph ace outside, carved an exquisite drop shot and, one point later, served another, more subtle ace, this one 109 mph out wide. It was a swift and astonishing display of range, and it drastically altered the arc of the match.

Reaching back for some blinding, vintage form, Serena recorded 20 aces -- implausibly equaling, according to the WTA, the highest total of her career. Thus, the hometown girl from nearby Palm Beach Gardens won 7-5, 6-3.

Next up: The winner of the Caroline Wozniacki-Yanina Wickmayer match in the quarterfinals.

The only previous time Serena hit 20 aces was the 2009 Wimbledon semifinal against Elena Dementieva -- and that was decided with an 8-6 third set.

Twenty aces? In two sets?

"I know," she said, crossing her eyes and making a funny face.

Why now?

"I don't know," she answered. "I'm not even going to ask. That was kind of crazy, though, I was like, 'Really?' That's kind of all I have to say about that is, 'Really? Are you sure?'

"My serve was hot. I was like, 'That's pretty cool.'"

Serena has made a living of wandering off the reservation for months at a time because of injuries or lack of interest -- and then flinging herself back into the fray of major championships. Last year, after some serious health scares, she came back in time for Wimbledon, lost in the fourth round then worked her way to the final in New York before Stosur -- channeling Marat Safin and his 2000 U.S. Open shocker over Pete Sampras -- played the match of her life.

At the age of 30, approaching AARP status in the world of professional tennis, Serena is finding it more difficult to instantly summon her championship form. She lost in the fourth round of the Australian Open back in January, which was the last time we saw her in a WTA event.

When she met Zhang Shuai in her first match here, Serena was admittedly nervous.

"Last time I played," she said, "I played horrible. My worst fear was as long as I don't hit a ball in the stands, I'll be good. I didn't do that, so it worked out well for me."

With all the attention focused on her sister, Venus, who is trying to play her way through a debilitating autoimmune disease, Serena has been quietly forceful as she moves through the draw. And how about that drop shot?

"I have a good drop shot," Serena said, a little defensively. "I never use it. I don't know why."

Stosur, to her credit, played better than the score might indicate. She finds herself in the odd post-major-victory zone that has plagued some recent champions. Ana Ivanovic won the French Open four years ago and is just now working her way back to the top. Li Na's game sort of vaporized after winning at Roland Garros last year and 2011 Wimbledon champion Petra Kvitova lost two of her three matches at Indian Wells and Miami -- hardly befitting the No. 3 player in the world.

Stosur, who turns 28 this week, is now a ho-hum 18-12 since winning the U.S. Open; she was lucky to even reach the fourth round here. Stosur was down 6-2, 5-2 in third-round match against Chanelle Scheepers and escaped by winning 10 games in a row. Still, with the emergence of so many younger athletes -- most notably Victoria Azarenka -- it is not unfair to wonder if she will ever win another major.

The same is probably not true for Serena.

She looks like she's still got the chops to compete at the highest level. And, perhaps after being sidelined for so long, she has learning to love the sport at which she excels. Serena jumped for joy after beating Stosur and is destined to return to the top 10.

She's a four-time Sony Ericsson Open here, going back a full decade to when she won here as a 20-year-old. With Venus playing Ivanovic late Monday night, there is a chance that both sisters would reach the quarterfinals. Just like old times.

"I hope so," Serena said. "We've both been through a lot."