World number one Tiger Woods made three birdies in four holes to grab a share of the lead as he made the turn in Friday's second round of the 77th Masters.
Top-ranked Woods, a 14-time major winner and four-time Masters champion, birdied the par-4 fifth and seventh and the par-5 eighth to stand on five-under with the back nine yet to play at formidable Augusta National Golf Club.
Also on five-under were Mark Leishman, trying to become the first Australian to win the Masters, and 53-year-old American Fred Couples, the 1992 Masters winner who closed with a birdie to grab the 36-hole clubhouse lead at 139.
A Leishman bogey at the 14th dropped him out of sole possession of the lead.
It was the first birdie at the fifth for Woods since his most recent Masters triumph in 2005 as he tries to win his first major title since the 2008 US Open and signal a full return from his slide to 58th in the world rankings.
How well Woods performs could decide whether or not Chinese 14-year-old Guan Tianlang makes the cut for the weekend after the Asian schoolboy was hit with a seldom-imposed penalty for slow play.
After taking the extra stroke for a bogey at 17, Guan finished on 75 in the second round and on four-over 148 for 36 holes, right on the edge of cut line, which includes the top 50 and level or anyone within 10 strokes of the lead.
"I respect the decision they make," Guan said. "This still is a wonderful experience for me. I have enjoyed playing in the Masters and I think I did a pretty good job."
Guan became the first player punished for slow play in a major since American Steve Lowery at the 2004 PGA Championship.
"Today is pretty hard because if you're timed only 40 seconds, it's pretty hard because you need to make the decision," Guan said. "The wind switched a lot."
One day after 45 players fired par or better at Augusta National, wind and tougher pin positions over the 7,435-yard layout kept the world's top golfers struggling simply to hold their positions.
"It's a hard course out there," Couples said. "I felt very good about what I shot. I had a couple little hiccups and did some other good things to shoot my score. But you know, the golf course is winning today.
"They put most of the pins in, I thought, really hard spots."
Leishman, who shared the first-round lead with Spain's Sergio Garcia on 66, took bogeys at the par-3 fourth and sixth holes but answered with birdies on the par-4 seventh and par-5 eighth until faltering on the back side.
Argentina's Angel Cabrera birdied five of the last six holes to fire a 69 and finish on 140 while Australia's Adam Scott, England's David Lynn and American Jason Dufner were in the clubhouse on 141.
A group on 142 for 36 holes included Germany's Bernhard Langer, the 1985 and 1993 Masters winner, Spaniards Sergio Garcia and Gonzalo Fernandez-Castano and Northern Ireland's Rory McIlroy, whose round of 70 included an eagle at eight.
"Digging in and grinding it out was pleasing for me," McIlroy said. "The eagle on the eighth really got me going. A 70 was a good score today. You had to be really disciplined.
"When we teed off it was rainy and windy. The wind was in a real unusual direction. It's a tough enough course as it is without wind like that."
Dustin Johnson opened with a five-under par 67, the best round of his career at Augusta National, but was a victim of Friday's tougher conditions by the end, playing the last five holes in six-over after having led by two strokes.
"The course is very tricky today, some pretty challenging pin positions," 2008 Masters champion Trevor Immelman of South Africa said. "I fought as hard as I could when I was out there."