Cole Hammer had the shortest match and the Americans made quick work of Great Britain & Ireland to win eight of 10 singles matches Sunday as they rallied for a 15½-10½ victory in the Walker Cup.
Nathaniel Crosby's side were 7-5 down after the first day of play but responded magnificently on day two to clinch the morning foursomes 2½-1½ and the afternoon singles 8-2 to run out comfortable winners.
American John Pak was the only player to go unbeaten across the two days, winning his singles match 2&1 over Euan Walker.
Sandy Scott then took out the US Amateur champion Andy Ogletree after a thrilling affair which saw the young Scotsman fire six birdies, finally seeing off the American with a par at the last for an important 1 up victory.
The USA retains the trophy after their 19-7 win at Los Angeles Country Club two years ago and now leads the overall series 37-9-1.
The U.S Walker Cup team came from behind with a dominant display in the singles at Royal Liverpool as the won for the first time in 12 years on foreign soil.
But the loss of three holes in a row from the 11 proved to be pivotal as the Americans claimed their first point of the match.
John Augenstein of Owensboro, Ky., scored the winning point with a 4-and-3 victory over Thomas Plumb of England.
Great Britain and Ireland captain Craig Watson consoles Alex Fitzpatrick after he lost his singles match
Scott and Walker rescued a half point for GB&I after chasing Augenstein and Ogletree for much of their foursomes match.
Although they dropped a hole at the 12, a birdie on the 15 restored their two-hole lead and they never looked back to give the visiting team its second point.
"We feel a little dejected that we didn't get that last match", USA captain Nathaniel Crosby said.
In the final foursomes Alex Smalley and Brandon Wu of the us never really looked in trouble in their match against Thomas Plumb and Tom Sloman.
With two matches left out on the course, Caolan Rafferty regained the lead for the home side with a 2&1 win over Alez Smalley and Conor Gough grabbed his second point of the day, beating Isaiah Salinda by two holes, to leave Craig Watson's s GB&I side with a two point lead going into day two.
The away side pulled another point back after Pak edged out Amateur champion James Sugrue, who did not feature in the morning foursomes - and only arrived on the tee two minutes before his match was due to start - by one hole.
Casey started the final round one shot behind Bernd Ritthammer and Robert MacIntyre and played bogey-free for his 14th title on the European Tour. Norman Xiong (3-0-1) also didn't lose a match.More news: Couple Arrested After Spending Spree, $120K Bank Error
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