Lyle, 164th on the PGA TOUR money list last year with $390,303, had an eagle and four birdies on the final six holes on the front nine and added birdies on Nos. 16 and 17 on the Jack Nicklaus-designed Tres Marias Golf Club course.
'I made a few solid pars to start with and then something happened,' said Lyle, who holed a wedge shot for eagle on the par-4 seventh. 'I kind of had the feeling at that point that it was going to be my day. I've had so many seconds and thirds and fourths that something had to snap eventually.
'With nine holes to go I knew it was going to be very hard for them to catch me. Not because I was ahead, but because of the way I was swinging the club. I hit a lot of great shots and my putter felt unbelievably good today. I know when it feels that good I'm going to hole a few putts.'
The 26-year-old Australian opened with rounds of 68, 69 and 67 en route to a 17-under 267 total. He earned $112,500 from the $625,000 purse.
'I came out here today to try and win my first tournament ever,' Lyle said. 'Today was by far the best I've played in a long time. I was never out of position. I was never in danger of making a bogey. It was one of those days when everything seemed to come together at the right time. This victory is for my family, who has been so supportive of me. I'm just a little sad they're not here to see it.'
Every finished with a 67.
Tom Johnson (68) was third at 11 under, Bubba Dickerson (67) followed at 9 under, and Steve Pate (67) and Greg Chalmers (72) tied for fifth at 8 under.