Serving to stay in the match, Navarro quickly fell behind 0-30.
Williams netted a crosscourt backhand to reach 15-30.
The American then struck a forceful crosscourt forehand which led to Navarro hitting a down the line forehand stab long to reach 15-40 and double match point.
Navarro then struck a backhand up the middle which Williams returned crosscourt from the forehand side for a winner to end the match after only 56 minutes of play.
For the day, the American struck 27 winners to 3 from Navarro.
Williams, who picked up her 8th career Miami title, has not lost a WTA Tour match this year going 17-0.
With his supercoach Boris Becker of Germany looking on from the stands, Djokovic recovered from trailing a break down at 1-2 in set one to the 4th seeded Andy Murray of Great Britain to lead 4-1 in the tiebreaker.
Murray then netted two down the line forehands before also netting a crosscourt backhand to drop the set.
In set two, Murray held serve to lead 5-4 as Djokovic served to stay in the set.
A double fault put the Serb down 0-30 before Murray struck a crosscourt forehand passing shot winner to reach triple set point at 0-40.
A crosscourt backhand return winner from Murray leveled the match at one set all.
However after dropping the middle set, the world number one quickly regrouped to out-steady Murray and take the last six games of the match.
The final two points of the match; two winners hit from Djokovic: a crosscourt backhand lob winner and a down the line backhand volley winner, demonstrated his variety of strokes which had served him well throughout the 7-6(7-3), 4-6, 6-0 contest.