Australia's Jason Day claimed a one-shot lead at the halfway stage of the Masters, but all the headlines were about two players at the opposite ends of the age spectrum on a dramatic day at Augusta National.
In the last group out, Day carded a 68 to finish six under par, one shot clear of compatriot Marc Leishman and 53-year-old former champion Fred Couples. And by failing to birdie the 18th, Day ensured Chinese teenager Guan Tianlang made the cut on four-over under the 10-shot rule, despite the 14-year-old earlier being penalised a shot for slow play.
Argentina's Angel Cabrera, the 2009 champion, was two off the lead alongside American duo Jim Furyk and Brandt Snedeker after storming home in 31 with five birdies in his last six holes, while English trio David Lynn, Lee Westwood and Justin Rose were another stroke back on three under.
Jason Dufner, KJ Choi, Adam Scott and Tiger Woods were also three under, 14-time major winner Woods dropping two shots in the last four holes by three-putting the 18th after seeing his pitch to the 15th hit the pin and bounce back into the water.
Couples, who claimed his only Green Jacket in 1992, also shared the lead with Dufner at the same stage last year but shot 75 on Saturday and eventually finished 12th.
Guan, the youngest player in Masters history, added a 75 to his opening 73 to finish four over par, but only after being controversially handed a one-shot penalty for slow play.
World number one Woods, who shared the lead before a back nine of 38, said of his bad luck on the 15th: "I was pretty p***ed. Looked like I was making birdie and now I have to struggle not to drop two shots. It was a good six but I played really well today and the round should have been in the 60s."
Rory McIlroy had an eagle on the eighth and birdie on the 18th in his round of 70 to lie two under, the same score as two-time winner Bernhard Langer after the 55-year-old completed a second consecutive 71.
Overnight joint-leader Sergio Garcia was 10 shots worse than his opening 66 to also finish two under, while American Dustin Johnson was the only player to reach seven under after 13 holes of his round, only to play the last five holes in six over par.
Defending champion Bubba Watson scraped into the weekend on four over after a 73, but Ian Poulter crashed out on seven over.