The unique format of the biennial team competition already ensures that players have a busy schedule but the backlog of matches caused by the torrential downpours has only added to their workload.
With some of Friday's matches held over until Saturday because of the intermittent showers, the players had to arrive at Muirfield Village Golf Club before dawn on Saturday to hit shots on the practice range.
They did not leave until after nightfall with play having spanned almost 12 hours and some players having competed in three different matches.
South Africa's Charl Schwartzel, who finished off a foursomes match, completed an entire fourball match, then played 12 holes of another foursomes match before bad light forced another stoppage, said he was exhausted by the end.
"We all felt like it," he said. "I was starting to hit a lot of shots to the right and that comes from a bit of fatigue."
The 2011 Masters champion played a total of 34 holes on Saturday, all with his countryman Louis Oosthuizen, and said he was relieved when a rules official told them it was too dark to continue.
"I was pretty happy not to go ahead and play," he said.
"It really is a long day, and it's a tough course to walk. Even 18 holes, it's a big walk around here. To go around it twice in wet conditions is tough."
The players are all facing another gruelling schedule on Sunday with four matches from Saturday still to be completed before the concluding 12 singles matches.
The United States finished the third day with a commanding five-point lead and needing just six more to retain the trophy but with 16 points still up for grabs on Sunday, the Internationals were not giving up hope.
"I know it's going to be tough tomorrow but we'll be rested," said Australian Jason Day.
"I think we'll still be a little bit tired but I think for the most part we'll be nice and rested on both our teams."
- Sports & Recreation
- Charl Schwartzel