Europe will take a three-point lead into the final day of the Solheim Cup, but three matches remained undecided due to Friday's weather delay and the painfully slow pace of play.
Seeking an unprecedented third straight victory, the home side won three of the morning foursomes to open up a commanding 8-4 lead at St Leon-Rot Golf Club in Germany.
However, Lexi Thompson and Cristie Kerr then beat Spanish pair Azahara Munoz and Carlota Ciganda in the opening fourballs match to cut the advantage to 8-5, and the United States led in two of the remaining three games when play was suspended due to the fading light.
World number three Stacy Lewis and Gerina Piller were one up after 16 against Caroline Masson and Caroline Hedwall, with rookie Alison Lee and Brittany Lincicome one up on the unbeaten Charley Hull and Suzann Pettersen after 15.
France's Karine Icher and Scotland's Catriona Matthew, who crucially birdied the 15th just before play was called off, were one up on Brittany Lang and Lizette Salas with three holes to play.
After the two fourball matches held over from Friday were halved on Saturday morning, Europe looked to have taken charge of the biennial contest by winning the second foursomes session 3-1.
England's Melissa Reid celebrated her 28th birthday by teaming up with Ciganda to beat Michelle Wie and Alison Lee 4&3, while Sandra Gal and Matthew won for the second time against Angela Stanford and Lincicome.
But the most remarkable point came from Pettersen and Hull, who were three down with four to play against Paula Creamer and Morgan Pressel, but birdied all four to snatch an unlikely victory.
“This is a robbery,” world number eight Pettersen said. “The greens are so soft I told Charley, let’s throw darts at the pins, stay aggressive.
“You just have to tell her to hit it right at the pin. She is awesome. It’s fantastic to play with her.”
Hull, 19, was an inch away from a hole-in-one on the 15th and holed from four feet on the 16th after a superb pitch from Pettersen from heavy rough.
Another birdie from close range on the 17th got the European pair all square for the first time since the second hole, setting the stage for Pettersen to hole from 10 feet on the 18th to complete a remarkable win.
Anna Nordqvist and Hedwall were the only home duo to suffer defeat, the Swedish pair losing 5&4 to a rejuvenated Lewis and Piller, who were an approximate seven under par.
US captain Juli Inkster and opposite number Carin Koch were then seen in animated conversation with European assistant captain Annika Sorenstam, with a disagreement over how advice is communicated to players understood to be the cause.
Only the captain can give advice to players during the competition, unless the captain designates someone to take her place in that role.
Inkster initially claimed she had been inviting Koch and Sorenstam to Thanksgiving dinner, but later told GolfChannel.com: “We had a discussion about the captain’s agreement. It’s over now.”
Koch was similarly keen to gloss over the issue, but a similar dispute occurred two years ago when American players complained that Sorenstam told a European caddie to concede a putt to Creamer so she could not show team-mate Thompson the line for a more important birdie putt.
“It happened this morning,” Sorenstam said. “It’s over. Move on.”