Calc fired rounds of 65-60-64-67 to run away with his third career Phoenix Open title. He bettered his nearest competitor, Rocco Mediate, by eight strokes.
Calcavecchia topped Mike Souchak's record aggregate score of 257, set at the 1955 Texas Open. He also tied John Huston's 28-under-par pinnacle set at the 1998 Hawaiian Open.
In addition to etching his name into the PGA Tour record book, Calcavecchia collects his 10th career Tour triumph, and his first since 1998.
'It's been a long time. At least it seems like it's been a long time,' said Calcavecchia, whose last win came at the '98 Honda Classic.
Due to a Saturday hailstorm, Calcavecchia and the rest of the 71-man field were forced to complete their third rounds at 8:00am local time Sunday morning.
Continuing the stellar play that had given him an overnight advantage of five strokes, Calcavecchia carded six birdies and one bogey over the final ten holes of his third round to open up a six-shot lead at 24-under-par.
With just a ten-minute break between rounds, Calcavecchia maintained his march to history by nearly holing both an approach shot to the first hole and his tee shot to the fourth. The pair of tap-in birdies carried Calc to 26-under-par for the event.
That's when the assault appeared to end. Calcavecchia bogeyed the fifth and 11th holes to fall to 24-under-par. Following pars at the 12th and 13th holes, he needed to play the final five-holes in five-under to break Huston's record, and in four-under to break Souchak's mark.
Calc returned to form by birdying the 14th hole. He then added another birdie at the 15th. And when a 12-foot birdie putt fell at the par-three 16th, Calcavecchia was in prime position to surpass both historical numbers.
Yet one more birdie ensued at the 17th. It was Calcavecchia's 32nd birdie of the tournament, breaking the 72-hole PGA Tour record of 31 set by Huston in Hawaii.
Needing a par at the last to break Souchak's record and a birdie to break Huston's, Calc had to settle for the former, as he two-putted from 25 feet.
'I've looked at (Souchak's) record before. But it never crossed my mind I could do something like that,' Calcavecchia said.
'I know I'm streaky, but I'm not that good. Looking at the board when I was out on the green and seeing a red 28, it just looked crazy.'
Calcavecchia is no stranger to going low and winning big. Calc was 27-under through four rounds of the five-round Bob Hope Chrysler Classic in 1997. He won the '89 Phoenix Open by seven shots, and the '92 event by five strokes.
News, Notes and Numbers
*Calcavecchia set a new Phoenix Open scoring record. His 256 total breaks that of Steve Jones (258) set in 1997.
*Calcavecchia's back-to-back rounds of 60-64 (124) in the second and third rounds broke the all-time PGA Tour 36-hole aggregate scoring record by one shot.
*Rocco Mediate, who won the 1999 Phoenix Open, recorded his second straight runner-up finish by shooting a final-round 69.
*Tiger Woods carded a final-round 6-under-par 65 to finish in a tie for fifth with Chris DiMarco. DiMarco, who shot 71 on Sunday, employs the same claw-like putting grip used by Calcavecchia.
*Defending champion Tom Lehman tied Steve Stricker for seventh place.
*John Daly shot 5-under-par 66 in the final round to tie for ninth. It's his first top-10 finish on the PGA Tour since the '98 Honda Classic, which was won by Calcavecchia.
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