The Briton will go on to face Spain’s Carlos Alcaraz in the next round.
Murray followed Emma Raducanu onto the main show court in the Californian desert after the teenager had lost her first match since becoming US Open champion in sensational style last month.
The 35-year-old fared much better than his compatriot as he delivered the sort of tennis that used to see him win grand slams before needing a metal hip in a 6-3 6-2 win over Frenchman Mannarino.
It was more evidence that Murray’s desire to compete at the top of the game may be possible as the fruits of a sustained run of matches on the ATP Tour are beginning to show.
Mannarino, ranked 50 in the world, is a tricky opponent, but one the Scot will be expected to beat if he is to get back up the rankings and he will now face a much tougher test against Spaniard Carlos Alcaraz, another teenager who enjoyed a breakout run at the US Open last month.
Perhaps Murray felt at ease having been reunited with his wedding ring, which was safely bound to his shoelaces again after its disappearance earlier in the week.
Murray’s band was tied to his shoes, which he left under a car to dry overnight only for them to go missing, prompting a successful social media campaign to see it returned.
The Scot also found his best tennis as he dominated Mannarino from the off.
The decisive moment in the first set came at 2-2 as he produced some vintage play as the former world number one converted a backhand lob on the run to set up break point which was converted after Mannarino dumped a short ball into the net.
Murray served out the first set without issue and was able to strengthen his grip on the match early in the second.
After fending off two break points he was able to take Mannarino’s serve in the next game, completing the break with a searing return of serve.
A double fault handed Murray a second break, allowing him to come through a nervy service game to complete victory in routine style.