Six of the past seven editions have been won by the home side.

Harrington, 48, has played in six Ryder Cups and will captain Europe against the USA next year at Whistling Straits, Wisconsin.

"Forty, 50 years down the road, it will probably be best to have a neutral set-up," said the Irish three-time major winner.

"Then there is no setting up a golf course as we did in Europe (at Le Golf National) so that it was very tight off the tee and par was a very good score.

"If you went back to Hazeltine, it was more of a birdie-fest."

Since the "miracle of Medinah" in 2012 when Europe came from 10-4 down to beat the USA 14.5-13.5, the Ryder Cups have all been comfortable home wins.

Europe won 16.5-11.5 at Gleneagles in 2014, the USA triumphed 17-11 at Hazeltine, Minnesota, in 2016, and Thomas Bjorn's team enjoyed a 17.5-10.5 success at Le Golf National in France last year.

Home captains can set up courses to suit their players.

But Harrington, speaking at an event to mark one year to go before the 2020 Ryder Cup, said Whistling Straits, on the shores of Lake Michigan, will not be as easy to alter for USA captain Steve Stricker.

"This is a much more natural golf course," said Harrington. "I'm interested to see down the road what Steve has in store, but it doesn't look like you can do a lot with this golf course.

"It looks like it's in a natural setting and the weather could be very changeable the week of the Ryder Cup.

"This is going to be a golf course that tests the players on its own merits."

The 2020 Ryder Cup will take place from 25 to 27 September, with television highlights and radio commentary on the BBC.