Second seed Sharapova opened her campaign on Monday with the same scoreline against fellow Russian Olga Puchkova and completed 92nd-ranked Doi's humiliation in 47 minutes.
"I didn't offer candy today," Sharapova, who launched a sweet making business last year, said.
"It's not really the statistic I want to be known for. I want to be known for winning grand slam titles, not that I won two matches 6-0 6-0."
The ruthless Russian played down her lack of competition to sharpen her game and said she had never been tempted to take her foot off the gas against the 92nd-ranked Doi, who managed to cobble only 15 points from the match.
"My focus is always on the next point and to try to win as many of them as possible," said Sharapova, who suffered neck and collarbone pain in the lead-up but was in full flight as she unleashed 16 raking winners.
"When you have your chances and opportunities, little doors that open up, you try to take them.
"I don't want anyone to know what score it is on the scoreboard just by looking at my face or my attitude. I try to play every single point like I really need to win it."
Sharapova, bidding for a fifth major trophy and a second Down Under, has spent only 102 minutes on court at Melbourne Park so far but will face a much stiffer test against seven-times Grand Slam champion Venus Williams in the next round.
The American defeated France's Alize Cornet 6-3 6-3.
The 25th seed lost the first two games of the match but responded well and then went down a break of serve early in the second set before winning the last four games of the match.
Asked about her prospects against Sharapova, Williams said: "I better bring my best game against her."
Sharapova holds a 4-3 head-to-head career advantage but the American has won their only two Grand Slam meetings in straight sets.
Australia's Samantha Stosur blew a 5-2 lead in the final set to continue her dismal run in her home Slam, losing 6-4 1-6 7-5 to China's Zheng Jie.
Stosur, US Open champion in 2011, was serving for the match before her nerves seemed to get the better of her, allowing Zheng to claw her way back and reel off five successive games to clinch a place in the third round against Julia Goerges.
The 28-year-old Stosur had minor ankle surgery late last year and lost in the opening round of both the Brisbane and Sydney tournaments before the start of the Australian Open.
Stosur, who lost to Zheng in the first round at Sydney last week, handed victory to her Chinese opponent when she double faulted on match point. Stosur has never advanced past the fourth round at Melbourne Park.
"Obviously it's a pretty hard one to take when you get yourself well and truly into a winning position (and) playing really quite well," Stosur said. "Then all of a sudden you get to 5-2 and you lose five games straight.
"Whatever word you want to put on it. At 5-2 up in the third, double break probably is a bit of a choke, yeah."
Agnieszka Radwanska continued her 2013 unbeaten streak, extending it to 11 matches, with a comfortable 6-3 6-3 second round victory over Romania's Irina-Camelia Begu.
The world number four, who won the Auckland and Sydney tournaments before the Grand Slam began and is yet to drop a set this year, will now meet Heather Watson in the third round after she beat Ksenia Pervak 4-6 7-6(7) 6-2, saving three match points in the process.
Despite her hot form Radwanska, who won both the Auckland and Sydney titles before the year's first Grand Slam, is not quite sure if she's playing as well as she can.
"I hope not," she said with a broad grin when asked if she was in the form of her life.
"Then I can play even better.
"I'm definitely happy that I'm playing my best tennis at the start of the year which is always tough after a few weeks just practising.
"(But) playing matches is always different and I didn't really expect to win that many matches in a row and hopefully I can keep going."
Fifth seed Angelique Kerber also advanced to the third round when she managed to overcome a feisty Lucie Hradecka 6-3 6-1 in 69 minutes.
Kerber, like Radwanska, dropped the first service game of the match before clicking into gear in the second set and sealing a clash against either American wild card Madison Keys with an ace.
The German left-hander has also quietly moved into contention in the Grand Slams, accumulating rankings points with a series of semi-final appearances. She also won her first WTA career titles, in Paris and Copenhagen, last year and won eight times against women ranked in the top-10.
"I have a lot of confidence from the last year," she said after her victory over Hradecka. "I beat a lot of good players and reached the top 10, top five. "I'm just enjoy(ing) where I am right now."
Another seed to progress on the third day of action at Melbourne Park was former French Open champion and Australian Open finalist in 2011 Li Na.
The Chinese sixth seed downed Olga Govortsova of Belarus 6-2 7-5 to book her place in the second round, where she will meet Sorana Cirstea, the Romanian 27th seed coming back from a set down to beat Kristyna Pliskova 1-6 6-3 6-2.
Other seeds to progress were Marion Bartoli, Ekaterina Makarova and former Serb number ones Ana Ivanovic and Jelena Jankovic but Dominika Cibulkova and Klara Zakopalova joined Stosur and Paszek as seeded casualties.