European Ryder Cup captain Padraig Harrington has issued an ultimatum to anyone hoping to be a wildcard pick on next year's team: turn up and play at Wentworth the week before the biennial tournament or forget about being on the Sunday night flight to Whistling Straits.

Harrington wants his prospective picks for the 2020 edition to show some hunger, not to mention form, at the tour's flagship BMW PGA Championship in Surrey.

"Nobody has an excuse not to turn up," the Dubliner said ahead of Thursday's the opening round of the US PGA Championship at Bethpage Black.

"They can't say they're playing another event or they're somewhere else... or want to rest.

"If you want a pick you're going to have to turn up and play a big tournament with the other players who are interested in that pick, so I can make a difficult decision as late as a week before (the Ryder Cup)."

Harrington announced recently that he would reduce the number of wildcard picks from four to three players.

He argued that the number nine on the qualifying list is usually selected anyway, but is likely to feel more comfortable if he has qualified automatically rather than being reliant on a captain's pick.

Not that any of the captain's picks last year - Spaniard Sergio Garcia, Swede Henrik Stenson and Englishmen Paul Casey and Ian Poulter - appeared ill at ease at Le Golf National, where Europe continued its two-decade long home dominance with a seven-point drubbing of the United States.

The biennial team event will be played next year from 25-27 September at the Whistling Straits course that hugs Lake Michigan in Wisconsin.

Harrington also feels strongly that to be eligible for Ryder Cup selection a player has to be a European Tour member in the two years preceding the event.

The issue had become a talking point because European four-times major winner Rory McIlroy indicated late last year that he might let his membership lapse in 2019 to focus on the PGA Tour in the US.

McIlroy, however, diffused the issue recently by confirming he would remain a tour member this year after all.

"It is nice that he has taken membership to put it down on paper and make things a little simpler and less complicated," Harrington said.

"I would be on the side of making the players jump through a few more hoops to be on the Ryder Cup team."