The teams were tied 5-5 after trading session sweeps over the first two days but the Americans showed no ill effects from being shut out on Friday at Royal Montreal Golf Club and moved back in front.
World number one Scottie Scheffler, paired with Collin Morikawa, was without a birdie through his first 15 holes but stepped up when it mattered most to secure the first U.S. point of the day.
Scheffler drained a seven-foot birdie at the par-four 16th and added another from just off the green at the par-three 17th to give him and Morikawa a 2&1 win over Australian Adam Scott and Canada's Taylor Pendrith.
"I was able to make a couple birdies when my partner needed me because he was a bit alone out there for a while today, so I was proud to step up when I needed to," said Scheffler.
The Internationals, desperate to beat the Americans for the first time since 1998, then drew level when the South Korean duo of Kim Si-woo and Tom Kim earned a 4&3 win over U.S. Ryder Cup captain Keegan Bradley and Wyndham Clark.
But Xander Schauffele and Tony Finau put the US back in front with a 3&2 win over Canadians Corey Conners and Mackenzie Hughes in a match the Americans never trailed.
In the day's anchor match, Patrick Cantlay chipped in for eagle at the par-5 12th to go 2-up and added three late birdies to maintain the cushion as he and Sam Burns earned a 2&1 win over Japan's Hideki Matsuyama and South Korean Im Sung-jae.
Third round action of the biennial event was interrupted by a roughly 90-minute fog delay that saw players removed from the course about 25 minutes after play began.
