U.S. Ryder Cup captain Zach Johnson may have had support from his players but he returned home under attack from almost every other corner after his team were humbled by Europe.

In sport there is always plenty of second guessing from fans but Johnson's decision-making was under intense scrutiny long before the first ball was struck at Rome's Marco Simone Golf Club and continued to build throughout the competition.

Johnson has been criticised by golf pundits and roasted on social media as the worst U.S. Ryder Cup captain ever.

For three decades Europe have been unbeatable on home soil and Johnson is just the latest to fail to return home with the coveted gold trophy after the U.S. lost 16-1/2 to 11-1/2.

But the manner of defeat left many American fans fuming.

"So four years from now we'll learn from it and hopefully we can implement a better process, certainly, than I did," offered a contrite Johnson on Sunday. "I love playing in front of our fans. I know these guys would probably say the same thing.

"But there's something special about coming over here and having to fight because it's hard, and I like the fight.

"So I wouldn't change anything."

But changes are expected before the next Ryder Cup in 2025 that the Americans will host at Bethpage Black in Farmingdale, New York before they get an opportunity in 2027 to end their European frustrations when The Golf Course at Adare Manor in County Limerick, Ireland stages the biennial event.

Johnson's leadership and decisions were questioned from the moment he made his captain's selections and how he prepared the U.S. for golf's most prestigious team competition, with many of his players taking a five weeks off.

The rumblings of concern exploded after day one when his men were swept in the morning foursomes session on Friday after sitting down some of his big guns and major winners Brooks Koepka, Jordan Spieth and Justin Thomas.

Trailing 6-1/2 to 1-1/2 after the first day, the knives were out for Johnson as the U.S. were put in a hole they could not climb out of.

"We're going to learn from this," assured Johnson. "That's what Team USA does. We reflect, diagnose and try to figure out what we can do better to make it more efficient.

"It's not anything other than that.

"There's no perfect formula to it. The formula this week is they got off to a great start, and that momentum led them into a pretty nice lead going into today (Sunday).

"Our boys fought like madmen and made it interesting, you know, made them earn it."