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A scintillating round of 64 from world number one Jordan Spieth gave him a four-shot second-round lead at the Hyundai Tournament of Champions in Hawaii.
Spieth, who started the day one shot behind first-round leader Patrick Reed, fired seven birdies and an eagle to go round in nine under par, 16 for the tournament.
The 22-year-old Texan went out in just 31 shots and is bogey-free in his first two rounds, looking a good bet to open the 2016 season with a seventh PGA Tour win.
"It was a similar round to yesterday," he said. "It is nice to have no blemishes on the card. I want to prepare and start the year with a bang, but I'm only through 36 holes, there's a long way to go.
"Sixteen under will be difficult to duplicate. For me it comes down to no bogeys, if I can keep them down then there is enough easy holes to get a good score."
Spieth disposed of Reed at the top of the leaderboard after the latter failed to match his first-round form, shooting 69 - four more than yesterday's round.
Reed is tied in second position with Kevin Kisner and Fabian Gomez at 12 under after both men made significant ground in the field.
Kisner went round in nine under while Gomez shot seven under to surge up the leaderboard.
Rickie Fowler is a further two shots back after firing six birdies in 67, while Bubba Watson is at nine under, with both men needing exceptional weekends if they are to catch Spieth.
Scotland's Russell Knox is tied in 21st - along with Jason Day - on three under while Graeme McDowell is a further two shots back in 29th.