INCHEON, South Korea — Phil Mickelson and Zach Johnson won the only match that reached the 18th hole Thursday, the final touch on another dominant day for the Americans in the Presidents Cup.

The rest of the foursomes matches were not much of a contest as the Americans built a 4-1 lead after the opening session.

It was the fifth straight time the Americans have taken the lead in the opening round of this one-sided contest, and the three-point lead was their largest margin since they had a four-point lead in 2007.

The Americans are going for their sixth straight victory, and after one day at the Jack Nicklaus Golf Club Korea, there was a familiar feel to the event.

The South African duo of Louis Oosthuizen and Branden Grace won the only match for the International side, taking advantage of a few poor shots by Matt Kuchar to seize control on the back nine for a 3-and-2 win over Kuchar and Patrick Reed.

It was the first point for Grace, who went 0-4 two years ago at Muirfield Village in Ohio.

“I know we’re behind,” Grace said. “But one point is better than none.”

Even so, this was another strong display by the U.S., which never trailed in the other four matches and has lost only one time in the Presidents Cup since it began in 1994.