Luke Donald defended Jon Rahm after the US PGA champion Brooks Koepka appeared to accuse the Spaniard of behaving like a “child” in the immediate aftermath of a bruising opening day for the United States at the Ryder Cup.

Rahm holed out dramatically on the final green so that he and Nicolai Højgaard could salvage half a point against Koepka and Scottie Scheffler. Europe lead 6½ to 1½ in Rome with the US failing to win a single match in a day for the first time in Ryder Cup history.

“I want to hit a board and pout just like Jon Rahm did,” said Koepka. “But, you know, it is what it is. Act like a child. But we’re adults. We move on.” Koepka supplied no further context about what he meant.

Pressed on Koepka’s comments Donald, Europe’s captain, seemed bemused. “I certainly didn’t see any of that,” Donald said. “Jon was a big support system for Nicolai today. Jon is a passionate person but I didn’t see him acting any other way.”

Donald insisted it will be “back to business” for Europe despite holding such a commanding advantage. “It is an unbelievable start, an historic day but we want it to be an historic week,” said the Englishman. “The job is certainly not done. We will come back with the goal of winning the Saturday morning session. But what a day, the guys as you can imagine are in good spirits. You need your superstars firing, you need them playing well. Without that it is an uphill battle. They stepped up and did what they needed to do.”

Europe halved three afternoon fourball matches on the final green having earlier trailed in them all. “What we did going down 18 shows the determination, the grit, the perseverance of our team,” Donald added. “They never gave up.”

Zach Johnson, the US captain, suggested members of his team and backroom staff had been affected by illness in Italy. “I am grateful we have a team doctor,” Johnson said.