Jamie Donaldson was maintaining his challenge for a first World Golf Championships title as the final round of the WGC-Cadillac Championship began.
Three behind American Patrick Reed overnight, Donaldson secured a routine birdie at the par five first to advance to two under at Trump National Doral.
That was only two behind double US PGA Tour winner Reed, who also birdied the first but failed to get up-and-down at the next after missing the green with his approach.
US PGA Champion Jason Dufner was second having also gained a shot at the Blue Monster’s opening hole.
Donaldson sat alongside Dustin Johnson, Zach Johnson and Hunter Mahan in a share of third, but World Number One Tiger Woods had dropped back to level par after finding water with his approach to the fourth.
Three Europeans were alongside the 14-time Major winner, with Graeme McDowell one under through six and US Open Champion Justin Rose and Dubai Desert Classic winner Stephen Gallacher cutting through the field at five and four under for the day respectively.
Mahan and Dufner slipped down the leaderboard as they added to the huge total of balls in the water, which had long since passed 200 for the week.
Reed was having no such problems, however, following a birdie at the third with a gain from 15 feet at the fourth to sit six under par.
That was three ahead of Dustin Johnson, with former Masters Tournament winner Zach Johnson and Donaldson tied for third.
Reed appeared to be coasting to victory as nine straight pars kept him three clear, but the first hint of a wobble came at the 14th when he missed a par effort from inside five feet.
That left him two clear of Bubba Watson, who was four under for the day coming down the last, and Donaldson, who birdied the 14th from eight feet.
A brilliant approach to the 17th left Donaldson with a tap-in for birdie and reduced Reed’s lead to one.