|Losing just seven games in her first three matches, Sharapova has yet to be tested. (Getty Images)|
Sharapova, who completed the career Grand Slam earlier this year at the French Open, needed only 58 minutes at 90-degree Arthur Ashe Stadium to wrap up the win over Burdette, who will be a senior at Stanford this year.
Sharapova has not been tested so far this year at Flushing Meadows, losing a total of seven games over her first three matches.
|More on U.S. Open|
Since winning the U.S. Open in 2006, this is only the second time Sharapova has advanced to the round of 16.
Defending U.S. Open champion Samantha Stosur cruised into the fourth round of the U.S. Open, where she will face a teenager who has defeated former Grand Slam winners in her last two matches.
Eighteen-year-old Brit Laura Robson, who ended Kim Clijsters' career two days earlier, knocked out 2011 French Open champ Li Na 6-4, 6-7 (5), 6-2 on Friday.
The 89th-ranked Robson had never been past the second round of a major tournament or beaten a top-10 opponent before this year's U.S. Open. Now she's done both after eliminating the ninth-seeded Li.
"She's obviously full of confidence and had two very, very good wins," Stosur said.
Stosur was pushed for the first time in this year's Open by American Varvara Lepchenko, but dominated the second set after winning the first in a tiebreaker.
The seventh-seeded Stosur won 7-6 (5), 6-2. She had dropped just five games through her first two matches.
It was still a successful Open for the 31st-seeded Lepchenko. After reaching at least the third round in three straight Grand Slam events, she'll likely climb into the top 30 in the rankings.
Robson put her hands to her head in shocked joy after the Chinese star returned her serve long on the final point.
She showed poise after failing to close out the match in the second-set tiebreaker, then overcoming two incorrect calls in the third set where she had to replay points she would've won if the initial ruling had been right.
With a break point on Li's serve at 2-2 in the final set, Robson's return clipped the baseline and Li hit the ball wide. But the line judge called Robson's shot out and, after a review overturned it, Robson lost the replayed point. Li won the next point as well to earn game point. But with the Louis Armstrong Stadium crowd roaring its support, Robson rallied back to get the break.
She became the next great British hope when she captured the 2008 Wimbledon girls title at age 14. Four years later, she seems to be reaching that potential, the youngest woman ranked in the top 100.
Robson is the first British woman to make the fourth round at a Grand Slam event since Sam Smith at 1998 Wimbledon.