At Thursday’s opening ceremony, Team Europe captain Harrington led applause to key workers in the USA and Europe.
The Irishman said: “The Ryder Cup is a special occasion but all things considered, has there ever been the prospect of a Ryder Cup quite as special as this one.
“After all the world has been through these past two years, it is such a joy and a relief to be standing here in front of you today and in front of so many of you.
“I admit there were times where I figured this might not happen. We all lived through this postponement 12 months ago, but even after the match was rescheduled there was talk about whether there would be any fans at all.
“You the fans make the Ryder Cup. We expect fans on both sides to be loud and vocal.
“So together, let’s make this the best Ryder Cup that there has ever been.”