Semple Thompson, who lives only a few miles from the Fox Chapel Golf Club, rolled in a 27-foot putt from the right fringe on the 18th hole to win her match against Vikki Laing 1-up and all but secure the title in the women's amateur version of the Ryder Cup.
The United States opened a 7-2 lead in the three foursomes and six singles matches Saturday before Britain & Ireland took five of the nine matches Sunday.
The Americans have won the biannual competition three consecutive times and hold a 23-6-3 lead in the series, but Britain & Ireland nearly staged a major comeback Sunday.
Britain & Ireland won two of the three foursomes in the morning, and at one time early in the afternoon led or was tied in all six singles matches.
Rebecca Hudson of Britain & Ireland defeated Mollie Fankhauser 3 and 1, and teammate Emma Duggleby won her match against Leigh Anne Hardin 4 and 3. That cut the U.S. lead to 8-6. It also set the stage for the 53-year-old Semple Thompson, the oldest player on the U.S. team and a winner in her foursomes match Saturday.
Semple Thompson went up a hole on Laing, perhaps the best player for Britain & Ireland, on No. 17, then hit her third shot to the right fringe on the par-5 18th green before making her putt.
Asked how far away the putt looked, she said, 'A mile.'
It may have helped that Semple Thompson, the defending U.S. senior women's champion, has played Fox Chapel numerous times. Still, she acknowledged being a little nervous when she saw Britain & Ireland doing so well early in the singles matches.
'It was very disconcerting,' said Semple Thompson, who was down three holes at one point on her front nine. 'But Vikki gave me a number of presents and I hit some good shots. The combination was lethal for her.'
Myerscough, who played at Arizona, was down five holes after the front nine but rallied to defeat Heather Stirling 2-up. Duncan, the defending U.S. Amateur champion, was playing behind Myerscough and defeated Alison Coffey 3 and 1.
Still, the star proved to be the hometown golfer.
'This ranks right up there as perhaps my greatest Curtis Cup experience,' said Semple Thompson, who has played in 12 Curtis Cups. 'I cannot imagine a better script.'