Federer was more worried about the playing surface than his opponent as he breezed past Santiago Giraldo of Colombia, 6-4, 6-3, 6-2.
Gael Monfils, Mardy Fish and Thomas Berdych also won in straight sets on a comfortable day for the big names in the men's draw. Serbia's Viktor Troicki was the only seeded player to lose.
Vera Zvonareva and Sharapova both progressed, as did Marion Bartoli and Sam Stosur, while Kvitova departed.
Federer joined Andre Agassi on 224 victorious singles matches at Grand Slam tournaments, putting them equal second, nine behind Jimmy Connor's record total. Federer will next play Israel's Dudi Sela.
However the third-seeded Swiss showed he was still eager for more challenges, complaining that organizers had made the courts too slow and too similar to those of the Australian Open; not providing enough variety for Federer's liking.
"Did they make a mistake? Maybe they did paint the court a bit too rough. It's just unfortunate that maybe all the Slams are too equal," the 16-time major champion said.
"They should feel very different to the Australian Open, and now I don't feel it really does. The night session just feels like you can take huge cuts at the ball, you can run everything down."
"It's great for tennis, but I'm not sure if it's really what the game needs. The game needs different speed at Slams and so forth. I don't feel we quite have that at the moment, especially if the US Open is getting slower."
Sharapova, shrieking as loudly as ever, came from a set and a break down against 19-year-old Heather Watson of Britain to win 3-6, 7-5, 6-3, improving to 12-0 this year in three-setters. Her second-round opponent will be Bulgaria''s Anastasiya Yakimova.
"It's just a matter of belief within myself, that no matter how well or bad or good I'm playing, or my opponent is playing, I know I can tough it out," the No. 3-seeded Sharapova said after her 2-hour victory.
"No matter what the situation is, I have the belief."
Sharapova will be eager to go one better than she did at Wimbledon, where she lost in the final to Kvitova. Fresh off that triumph, Kvitova," a 21-year-old from the Czech Republic seeded No. 5 in Flushing Meadows failed to follow it up, flopping at the U.S. Open with a 7-6 (3), 6-3 loss to 48th-ranked Alexandra Dulgheru of Romania.
Kvitova is the first reigning Wimbledon women's champion to lose her first match at the U.S. Open in the same season.
Only three times had the Wimbledon winner bowed out as early as the third round in New York: Sharapova in 2004, Conchita Martinez in 1994, and Billie Jean King in 1973.
"This is something new for me," Kvitova said about her new status as Grand Slam champion. "I've felt a little pressure."
The seeded men's casualty Troicki lost 3-6, 6-3, 4-6, 7-5, 7-5 against Alejandro Falla of Colombia.