* Bogey-free through two rounds
* Plunders par-fives again
* Putts brilliantly on slow greens (Recasts, adds quotes)
Jan 8 World number one Jordan Spieth delivered a putting masterclass on the way to a flawless nine-under-par 64 that took him four shots clear at the halfway stage of the Hyundai Tournament of Champions on Friday.
Spieth, who would match Tiger Woods with a seventh PGA win before the age of 23 should he finish top of the leaderboard on Sunday, putted brilliantly on greens he said were the slowest he had ever encountered on the PGA Tour.
Boosted by a 35-foot chip-in eagle at the par-five ninth, the Texan added seven birdies to post a 16-under 130 halfway total, with first round leader Patrick Reed (69), Kevin Kisner (65) and Fabian Gomez (66) tied for second on 12-under.
Spieth is also on track to beat the tournament record of 31-under set by Ernie Els in 2003, though he said the South African's mark was probably safe.
"I guess it's possible but that's asking a lot," Spieth told reporters at the Kapalua Plantation course on Maui. "(Another) 16-under will be difficult to duplicate.
"I don't know if I could have scored much better these first couple of days."
Should he lift the trophy on Sunday it would be 22-year-old's seventh victory on the PGA Tour, matching the number achieved by Woods before turning 23.
Only Horton Smith, who won 14 times from 1928-30, piled up more victories by that age.
Posting his second straight bogey-free round, Spieth plundered the par-fives, playing them in a total of five-under, and on the few occasions he was in danger of dropping a shot his flawless cross-handed putting came to the rescue.
He sank testing par-savers on the 16th and 17th holes and then finished his round in style, coaxing in a 13-foot birdie at the par-five 18th where his ball teetered on the edge of the cup before dropping in.
"It's nice to have no blemishes on the card," said the Masters and U.S. Open champion. "I started slapping it around (on) 16 and 17, but fortunately those saves really kept us on the go and allowed me to have that confidence on 18.
"Patience is going to be key this weekend. There's going to be a lot of birdies made.
"If I can continue to ... keep a blemish-free card, we're going to be in good position."
Spieth's putting impressed former Tour player Notah Begay, who told the Goldf Channel: "He's putting as well as anybody ever has in the history of the game".
(Reporting by Andrew Both in Cary, North Carolina; Editing by Peter Rutherford)