Perez bided his time and with the chequered flag waving, he duly delivered an impressive 1m 34.000s to jump ahead of Ferrari’s Kimi Raikkonen, with the sister Force India of Esteban Ocon 0.593s behind his pacesetting team mate to complete an unlikely top three.
The result means the fairytale start to the Silverstone squad’s new era continues, following their hugely impressive display in Belgium last time out under new team entry Racing Point Force India.
It was indeed also a surprise top six on show at Monza, with Toro Rosso’s Brendon Hartley coming home in fourth ahead of Red Bull’s Daniel Ricciardo and the sister Toro Rosso of Pierre Gasly.
Ricciardo will be chuffed to have finished in the top five, after he encountered problems with Renault’s hotly-anticipated ‘Spec C’ engine just a matter of minutes into the session. Team Principal Christian Horner, however, later revealed that there was no problem with the engine.
In the other RB14, Max Verstappen was running in P1 for a long period of time, but the Red Bull driver ultimately had to settle for P7 ahead of Renault's Carlos Sainz, while the sister yellow RS18 of Nico Hulkenberg edged Mercedes’ Valtteri Bottas, who completed the top 10.
All eyes were undoubtedly on Ferrari - running at their home Grand Prix this weekend - ahead of this opening practice, and the Italian squad endured a mixed session, with Sebastian Vettel managing just four laps and finishing down in 17th.
The German spent much of the session rooted to his garage, with the team opting for a change of gearbox, so he’ll be keen to get on track for more running when the action resumes later this afternoon.
His chief title rival Lewis Hamilton, currently leading the world championship race, also missed out a top-ten finish, with the Mercedes star managing just six laps to clock the 11th-quickest time on Friday morning.
Over at McLaren, Lando Norris was given another chance to participate in a Grand Prix weekend, this time the British teenager taking the seat of Stoffel Vandoorne. He finished bottom of the pile, 4.282s behind Perez, while the sister MCL33 of Fernando Alonso came home in 14th.
So what did we learn from the first 90 minutes of running in Italy? Not much perhaps, given the potentially unrepresentative conditions, but Force India won't forget Perez's late surge for P1. Plenty to look forward to then when the drivers return to action in FP2…