DeChambeau took the role of cheerleader on the first tee after being left out of the morning foursomes and saw his team-mates secure a 3-1 lead after Jon Rahm and Sergio Garcia had put the first point on the board.
But with US captain Steve Stricker sticking with his pre-determined plan, DeChambeau got the chance to earn his first Ryder Cup point – following three defeats on his debut in Paris – alongside rookie Scottie Scheffler in the afternoon fourballs.
An errant drive on the first struck a female spectator on the shin – it was not clear whether the traditional warning of fore was shouted – but DeChambeau still made birdie to halve the hole against Rahm and Tyrrell Hatton.
A par on the fourth was enough to edge the European pair ahead before DeChambeau cut the corner on the par-five fifth, unleashing the monstrous downwind drive which left him just 72 yards to the green and set up an approach to four feet for an easy eagle.
In the top match Dustin Johnson and Xander Schauffele were two up on Paul Casey and rookie Bernd Wiesberger after seven holes, but there was better early news for Europe elsewhere.
A fired-up Shane Lowry and Rory McIlroy were one up after five against Tony Finau and Harris English, while Tommy Fleetwood and Viktor Hovland led by the same margin after four holes against Justin Thomas and Patrick Cantlay.
Padraig Harrington’s side needed a strong afternoon performance after the morning’s results, with Johnson and Collin Morikawa beating Casey and Hovland 3 and 2 and Brooks Koepka and Daniel Berger defeating Lee Westwood and Matt Fitzpatrick 2 and 1.
McIlroy and Ian Poulter had at least avoided suffering a record defeat to Cantlay and Schauffele after losing the first five holes, but the eventual 5 and 3 loss was a demoralising blow for one of Europe’s star pairings.
Europe also lost the opening session 3-1 in Paris in 2018, albeit in fourballs, but won all four afternoon matches on their way to a comprehensive seven-point victory at Le Golf National.
Garcia already held the record for most points won in the Ryder Cup with 25.5 and Friday’s win was his 23rd overall, equalling the record held by Nick Faldo.
Rahm holed from almost 60 feet for birdie on the fourth and further birdies on the eighth and 10th put the European pair in command, with Garcia crucially holing from 25 feet for another on the 15th before Thomas missed from much closer.
The Americans won the 16th to keep the match alive and Jordan Spieth then played an extraordinary shot from thick rough on a steep bank to the left of the 17th green, the slope forcing him to turn and almost run into Lake Michigan as he struggled to keep his balance, only for Thomas to miss the par putt.
“I don’t think I exaggerated that fall, you know how steep that is,” Spieth said. “Once I started moving, I was like, I’ve got to keep moving until I find a flat spot.”
McIlroy and Poulter were two over par for the first five holes and in danger of suffering the heaviest ever defeat in a foursomes match, the largest margin of victory of 7 and 6 most recently achieved by Phil Mickelson and Keegan Bradley against Westwood and Luke Donald in 2012.
It took until the 10th hole for a superb pitch from Poulter to set up a first birdie of the day and par was good enough to win the next before Schauffele almost holed his tee shot on the par-three 12th.
The birdie was duly conceded but Poulter holed from nine feet for a half and both teams also birdied the next before two more birdies from the Americans sealed the win.
“The start wasn’t great,” McIlroy said. “I don’t know if anyone could have beat (sic) Xander and Patrick today. They played really good, four birdies in a row. They were a great pairing today and all you can do is praise them for the way they played.”