He gave his hometown gallery plenty to cheer about, matching his career-low round with a 7-under 63 to take the first-round lead in the Fry's Electronics Open on Thursday.
Nick Watney, Rich Beem and Frank Lickliter II were two strokes back, with Lickliter posting the day's only bogey-free round.
'It's nice just to have friends around out there,' said Allen, who lives about 10 minutes from the course. 'I had 20, 30, 40 friends out there yelling, and that's always really nice. You don't get that very often. So when you get things going, it's nice to have some fun.'
It wasn't as much fun for Grayhawk member Phil Mickelson, No. 2 on this year's money list and the biggest name in the tournament. Mickelson hit three balls into the desert and wound up at 1-over 71, eight strokes behind Allen.
'I felt like I played better than I scored,' Mickelson said. 'I didn't drive it terribly, but two or three loose swings cost me.'
Mickelson attracted the biggest flock of followers on a sunny, 81-degree day.
The first day of the new tournament had a more intimate feel than Scottsdale's other PGA TOUR event, the FBR Open, which has become a four-day corporate party just down the road at the TPC Scottsdale. There were open seats in the greenside bleachers and plenty of room to roam along the fairways.
Unlike some Fall Series events, this one drew a strong 132-player field, including Aaron Baddeley, Tom Lehman, John Daly, David Duval, Justin Leonard, Steve Elkington and Mark Calcavecchia.
The winner of the $5 million event will get $900,000.
The 48-year-old Allen has never won in 292 tour events. He matched his career-best finish as a runner-up in the Turning Stone Resort Championship last month.
Since the start of the Fall Series, Allen has made the biggest jump on the money list, from No. 154 to No. 93, a gain of 61 spots. He's earned $975,677 this year.
Like many of the players in the field, Allen is no stranger to Grayhawk's 7,125-yard Raptor Course, where he's played several non-tour events.
'I knew this was a week I would feel good at,' Allen said.
Allen teed off on the 10th hole and parred the first two holes. He birdied the 12th and 14th, then blasted in from a bunker for an eagle 2 on the 332-yard 15th hole.
On 16, Allen chipped in from 30 feet for a birdie. That left him 5 under after seven holes.
'That kind of got everything going,' Allen said. 'Obviously, I was in great shape after that.'
Allen finished with six birdies, an eagle and a bogey.
'I knew you could shoot some good scores out here, especially this time of the year, playing as short as it does,' Allen said.
Allen's 63 overshadowed the day's most interesting round, turned in by Watney.
Watney made a career-best 11 birdies.
He also posted an 8 on the par-4 seventh hole.
Not a bad result for his first time around the Raptor. Watney skipped the practice rounds and let his caddie, Tim Goodell, steer him.
'Maybe I've been doing it all wrong for the last three years,' Watney said.
Watney, who won his first PGA TOUR title in New Orleans this year, had thought about taking this week off after playing last weekend in Las Vegas.
'It crossed my mind,' he said. 'I don't know, it was just really tough to get motivated to come out here. I was really tired for some reason. But I'm glad I played now.'