By Mark Lamport-Stokes
DUBLIN, Ohio (Reuters) - Foursomes play at the Presidents Cup was set to resume at 5:45 p.m. local (2145 GMT) on Friday after a weather delay of just over two-and-a-half hours due to a thunderstorm had halted early United States dominance.
Though officials hope to get in a further one-and-a-half hours of play at rain-softened Muirfield Village Golf Club, the opening foursomes session was all but certain to spill over into Saturday when further thunderstorms have been forecast.
Phil Mickelson and Keegan Bradley had earlier staged a stirring comeback for the U.S. in the top match before torrential rain swept across the course and, as thunder rumbled overhead, the siren sounded at 3:09 p.m. to halt the action.
Seeking to win the trophy for an eighth time in 10 editions of the biennial team competition, the Americans led in three of the six matches, trailed in two and were all square in the other.
Mickelson and Bradley did well to go just one down after being outplayed by Australian Jason Day and Canada's Graham DeLaet over the first four holes, then won the fifth, sixth, seventh and eighth to go three up.
Left-hander Mickelson sparked the fightback by sinking a 15-foot eagle putt from the fringe at the par-five fifth before hitting a stunning approach to inside two feet at the par-four sixth in the alternate-shot format.
Cup veteran Steve Stricker and 20-year-old rookie Jordan Spieth were one up on South Africans Branden Grace and Richard Sterne after seven holes while Webb Simpson and Brandt Snedeker were all square with Argentina's Angel Cabrera and Australian Marc Leishman after six.
In the day's marquee match featuring two triumphant combinations from Thursday's opening fourball encounters, Tiger Woods and Matt Kuchar were one up on in-form South Africans Louis Oosthuizen and Charl Schwartzel after five holes.
World number one Woods set the tone for a contest of high quality when he struck his second shot to two feet for a conceded birdie at the par-four first. The next four holes were shared with a par, a birdie, a birdie and another birdie.
The Internationals, who have lost the last seven sessions of foursomes played at the Presidents Cup, had welcome blue numbers on the leaderboard in the second and last matches out.
South African Ernie Els and Zimbabwean Brendon de Jonge were three up on Bill Haas and Hunter Mahan after nine holes while Masters champion Adam Scott and Japan's Hideki Matsuyama were two up on Zach Johnson and Jason Dufner after five.
The United States, who have won the last four Presidents Cups, led by 3-1/2 points to 2-1/2 after Thursday's opening fourball matches when play was also interrupted by a thunderstorm.
(Reporting by Mark Lamport-Stokes; Editing by Gene Cherry)