Once she had claimed the first set with a late break of serve, she powered through the second, breaking twice before wrapping up the match with an ace.
"Practice and playing are so different and you can only prepare the best you can," Sharapova said.
"The reaction and anticipation you need are so hard to replicate in training and these are the things I need."
In the last eight, the 30-year-old faces Estonian qualifier Anett Kontaveit, who was a 2-6 7-6 (7-1) 6-1 victor over Spanish fifth seed Garbine Muguruza.
She may not have figured in any draw for 15 months, but it appears Sharapova still has a strong mental hold on so many of her opponents.
Makarova had a glorious chance to hit a backhand winner into open court to break for a 6-5 lead, but missed. She then dropped her serve to concede the set, and only won one more game after that.
It was another strong performance by Sharapova, and she then moved to the media centre to make it clear she no longer wishes to discuss the details of her positive test for meldonium.
She says she has done "numerous interviews in the past few months" - which overlooks the fact that journalists and publications, like the fashion magazine Vogue, have been very carefully selected.
Konta, meanwhile, admits her clay-court game is a work in progress, but thinks she is playing well enough to prove effective on the surface.
She says she needs to improve her movement and her point construction, but was not too downhearted by her start to the clay season. She has won two and lost two, and will next play in Madrid in 10 days time.