Perry shot a 2-under 68, and Pernice had a 70 to finish at 8-under 202 on Desert Mountain's Cochise Course.
The 60-year-old Haas, four strokes ahead after opening with rounds of 66 and 62 to break the tour record for consecutive rounds of par or better at 38, had a 75 to fall a shot behind. He had a double bogey, six bogeys and three birdies.
Bernhard Langer was tied for 10th at 4 under after a 70. Langer won the Charles Schwab Cup points title last week, has a tour-high five victories – two of them majors – and also has wrapped up the season money title with $2,916,189.