The American world number 10 offered Mello few chances to break in the 66-minute match, losing only 11 points in nine service games.
"I put in a good service performance," said Blake, who won his only title of the year at Sydney in January.
"I was able to dictate the whole time and I felt good about my game."
Blake will face fellow American Sam Querrey in the last eight after the teenager survived two match points before upsetting fifth-seeded Ivo Karlovic of Croatia 5-7 7-5 7-6.
"I don't think I've ever saved a match point on the ATP tour and won a match," said Querrey, who has beaten Karlovic both times they've played.
The 90th-ranked Querrey won the final two points of the tiebreaker to seal victory, hitting a forehand winner then benefiting from Karlovic netting a backhand return.
The 43rd-ranked Karlovic lost out on his second match point opportunity when serving at 6-5 in the third set tiebreaker by netting an inside out forehand.
COMPLETE MELTDOWN
Friday's other quarter-finals pit top-seeded Andy Roddick against sixth-seeded Lee Hyung-taik of South Korea, third-seeded Dmitry Tursunov of Russia against Japanese amateur Kei Nishikori, and Canada's Frank Dancevic against Igor Kunitsyn of Russia.
California-based Tursunov emerged with a 6-3 0-6 6-2 second-round victory over countryman Teimuraz Gabashvili, recovering to win after suffering a complete meltdown in the second set.
In the second game, Tursunov went up 30-0 but then lost the next four points as well as his cool. The lapse allowed Gabashvili to win 17 of the next 18 points on his way to setting up a decider.
"I'm not even sure what to say," Tursunov said.
"I was letting my emotions out a little bit. Most people say, 'why are you so quiet on the court' but once I let my emotions go, I get a little crazy."
Tursunov regrouped in the third set to break serve in the third and seventh games.
Japan's Nishikori, a 17-year-old amateur ranked 372nd in the world, moved into his first tour quarter-final with a 6-3 3-6 6-1 triumph over Michael Berrer of Germany.
Nishikori, who has trained at the famed Nick Bollettieri Tennis Academy in Florida for the past four years, blew the 83rd-ranked Berrer off the court in the final set by winning 20 of the final 27 points.
"I can't believe it," an overwhelmed Nishikori admitted.
"I came here and I'm just playing good. It's unbelievable."
