AUGUSTA, United States (AFP) — Jordan Spieth completed the greatest 36-hole start in Masters history yesterday, firing a six-under par 66 at Augusta National that matched him for the lowest halfway total in any major.

The 21-year-old American stood on 14-under 130 after two rounds, a bogey-free Friday giving Spieth a Masters midpoint record-matching five-stroke lead over compatriot Charley Hoffman.

“Any time you can set a record here is pretty awesome,” Spieth said. “I’m really excited about how I played.”

Fourth-ranked Spieth broke the Masters 36-hole low of 13-under 131 set by Ray Floyd in 1976 and nearly broke the low two-round major start of 130.

Spieth missed a seven-foot birdie putt at the 18th hole that would have put him on 129, settling for par to join the 130 group that includes England’s Nick Faldo from the 1992 British Open at Muirfield, American Brandt Snedeker from the 2002 British Open at Lytham and German Martin Kaymer at the 2014 US Open at Pinehurst.

“Didn’t know what any of these scores meant in history or anything like that,” Spieth said. “I just knew I had a good look at birdie and had a good read on it, and it was just barely off.”

Spieth, seeking his first major title after a runner-up Masters debut last year, shared the biggest 36-hole lead mark with Floyd in 1976, Jack Nicklaus in 1975 and Herman Keiser in 1946, after Hoffman closed a round of 68 with his lone bogey.

“I’m happy with the way I played,” Hoffman said. “I was going for a bogey-free round and unfortunately I didn’t close it out.”

Spieth’s 36-hole domination, with 15 birdies against one bogey, evoked memories of Tiger Woods’ record-setting 1997 Masters romp for his first major title. Woods will remain the youngest Masters champion by about five months even if Spieth wins this year.

“There’s a pretty big separation right there,” Woods said. “He has played beautifully.”

The record 36-hole Masters comeback to win is eight strokes by Jack Burke in 1956, but there are only four rivals to Spieth inside that margin, Hoffman and a pack at seven back — American Dustin Johnson and England’s Justin Rose and Paul Casey — and three-time Masters winner Phil Mickelson on 138.

Johnson fired a 67 that included a Masters one-round record of three eagles, coming at the par-5 second, eighth and 15th holes.

“I made a lot of great shots and then holed some putts,” Johnson said.

World number one Rory McIlroy and Woods, a 14-time major champion back after a two-month lay-off to work on his game, were each sharing 19th on 142, 12 adrift.

Woods fired a 69 and said he was “very proud of what I’ve done, to be able to dig it out the way I have”.

Woods, 39, has not won a Masters since 2005, has not won a major since the 2008 US Open and has not won any title since the 2013 WGC at Firestone.

McIlroy, expected to battle for a third major win in a row that would complete his career Grand Slam, flirted with the cut line but went five-under on the back side to finish on 71.

“I’m really proud of myself the way I fought back,” McIlroy said.

The hottest player in golf over the past month, Spieth won his second US PGA title in March at the Valspar Championship, took second at the Texas Open and Houston Open, then opened with a 64 Thursday to become the youngest first-round leader in Masters history.

Spieth pitched from 50 feet to inches from the cup to set up a birdie at the second, sank an 18-foot birdie putt at the fifth and birdied eight after finding a fairway bunker. Spieth made an 18-foot birdie putt at 10 and sank eight-footers for birdie at the par-5 13th and 15th.

Before green jacket fittings start, however, Spieth needs to close out the victory, something he could not do last year after leading Sunday on the front nine.

“It’s definitely going to play more challenging,” Spieth said. “I’m going to have to be more patient, be OK with a bogey here or there.”

Four-time major winner and two-time Masters runner-up Ernie Els, nine back on 139, has not given up on catching Spieth. The 45-year-old South African seeks a green jacket in his 21st attempt.

“It’s very impressive,” Els said. “It’s a long, long way from being finished. A lot of work to be done still.”