The Mexican was one of the quietest on track, logging just 43 laps to record a best of 1:33.105s.
That marker was the best of the test to date as teams begin to look at performance running ahead of next weekend's Bahrain Grand Prix.
Red Bull sat out the better part of the opening hour before Perez emerged from the garage, the Mexican promptly going fastest.
Zhou Guanyu was second best for Alfa Romeo Sauber, having briefly been sat atop the timesheets, recording a solid 82 laps.
Haas started the day an hour early, Kevin Magnussen completing 17 laps in the time given after the squad missed Thursday morning's running.
His progress was only halted after 33 laps, once the other teams had joined him on track, with a water pressure leak.
It proved a comparatively short delay of around 20 minutes and Magnussen was back on track with just over two hours remaining in the session.
However, his running was halted soon after with a fuel systems problem that left him in the garage with 38 laps to his name.
Williams returned after suffering a brake fire on the rear of the car on Friday morning, Nicholas Latifi back at the wheel.
Looking to make up for lost time, the Canadian completed 73 laps for a best time of 1:35.634s.
It was an encouraging performance from the Swiss squad, with solid laps early in the day for a team that has been short on mileage.
Lando Norris was also making up for lost time, and though his pace was far from electrifying he did for a period top the session in the early minutes.
However, with McLaren suffering brake issues and unable to complete any long running, he recorded just 39 laps in the session.
The highlight of the morning was provided by Pierre Gasly and Lewis Hamilton, the pair appearing to have almost been locked in a race battle for an extended period.
Hamilton trailed the AlphaTauri driver for a number of laps, but did shape up to pass on multiple occasions.
While the exchange needs to be taken with a grain of salt given the uncertainties regarding engine modes, fuel load and so on, it painted an encouraging picture that cars are indeed able to follow one another more closely.
Testing is set to continue in Bahrain with four more hours for most, plus an additional two hours for Haas at the end of the day.
Formula 1 pre-season testing Bahrain, Day 3 morning session
|Red Bull Racing
|Alfa Romeo Sauber