If you look at Sergio Perez lap times, they were not much different than Verstappen. The only time they were significantly different was before he was pitted because he was left out on his soft tires. It makes his fight that he put on Lewis that much more impressive.

From laps 2-17, Perez average 0.26 seconds per lap behind Verstappen

After he pitted on lap 22 (from laps 23 to 35) his average lap time was within 0.06 seconds of Verstappen.

After the next pit stop laps, 38 to 44 Perez average lap time was 0.31 sec/lap greater.