The Scottish pair secured a valuable half for Craig Watson’s team after staring defeat in the face in the second-day foursomes at the Hoylake venue.
They were behind from the fifth in a scrappy affair against Andy Ogletree and John Augenstein, the two finalists in last month’s US Amateur Championship at Pinehurst.
The tartan twosome made the only birdie of the match at the short 13th, but a bogey at the next left them two down with four to play on a lovely Merseyside morning.
At that stage, it looked as though the session was heading for a 3-1 win for the visitors, but, to the delight of a big crowd, Scott and Walker won both the 15th and 17th with pars.
It was advantage to the Americans after both teams had played their second shots at the last, but a brilliant lag putt from fully 40 feet by Walker secured the half.
The gutsy effort left GB&I leading 8.5-7.5, having started the day with a two-point cushion in their bid to reclaim the trophy after being hammered in Los Angeles two years ago.
English young guns Alex Fitzpatrick and Conor Gough both suffered their first defeats of the weekend as GB&I sole success came from Tom Sloman and Thomas Plumb in the bottom match.
With all 10 players in action in the concluding session, Scott faced unbeaten Brandon Wu while Walker tackled John Pak.
“We got a half in the last game,” said Watson of the contribution from his compatriots, “so obviously it’s going to be a boost for us.
“But, as we thought last night, it’s going to be close. It’s going to go probably right into the last game this afternoon as both teams are so even.”