Tiger Woods admitted he was "ticked off" after seeing his hopes of winning a third Players Championship title suffer a potentially fatal blow on the famous 17th hole at Sawgrass.
Woods began the second round five shots off the lead but had moved ominously up the leaderboard with birdies on the 12th, 13th and 16th, having started from the 10th tee.
However, the former world number one then dumped two balls into the water on the par-three 17th on his way to a damaging quadruple-bogey seven.
Woods had narrowly avoided the water on the 13th and 16th and made birdie on both occasions, but his luck ran out on the 17th when his tee shot pitched on the green but just trickled off the back edge.
The 43-year-old opted to play his next shot from the drop zone but a pulled approach took one bounce before plunging into the water and after finally finding the green, Woods two-putted from 20 feet.
"The second wedge didn't really surprise me, it was too flat. The first one I hit surprised me," Woods told reporters. "I was pretty ticked. I was determined to get it all back.
"Other than 17 I really haven't done a whole lot wrong. Anyone who makes the cut has a chance."
Woods regrouped to play his remaining 10 holes in two under par and return a 71, but on three under par he was six shots behind surprise clubhouse leader Jim Furyk, the 48-year-old former Ryder Cup captain carding eight birdies in a flawless 64.
"I've had some good weeks here, almost won five years ago, and I've also had some rough weeks here and that's the nature of this golf course," Furyk, who lives near the course, told Sky Sports.
"It's fun to be at home and have a lot of folks cheering. When this year started I didn't even expect to be in the field. I kind of squeaked in late but I've been playing well of late so it was nice to get that opportunity."
Furyk enjoyed a one-shot lead over fellow American Kevin Kisner and Australia's Jason Day, with Scotland's Russell Knox on six under par after what ultimately proved a disappointing 68.
Knox had covered the front nine in 32 and also birdied the 10th and 16th, but three-putted the 17th and also bogeyed the last after a wayward drive.