Competing chants of "U-S-A, U-S-A" and "Oles, Oles" echoed across the first tee box followed by a hushed silence which came over the gallery as Europe's Graeme McDowell hit the opening shot of the 2012 Ryder Cup.
McDowell and partner Rory McIlroy were part of the first foursomes of the Ryder Cup as they went up against Americans Jim Furyk and Brandt Snedeker.
After McDowell hammered his first shot slightly left, Furyk did the same for the Americans. Both teams parred the hole.
Furyk wore a black cap to protect against the chilly morning air at the Medinah Country Club course which is hosting the Ryder Cup for the first time.
The American players arrived to the tee box first which brought a massive cheer from the gallery which stood 15 deep in places. They were followed by the European duo of McIlroy and McDowell.
The players posed for pictures together, got a final kiss from the wives and girlfriends then got down to business.
One massive cheer went up on the US side when a course worker showed up with a bundle of US flags which he tossed into the gallery.
Despite their smaller numbers, European fans were just as vocal. One group dressed in blue and yellow with European flag jackets and pants sang "Old MacDonald Had a Farm".
"I have been looking forward to this for two years," said Europe fan David Boyle who flew to Chicago from Glasgow, Scotland for the event.
Boyle's friend David Dunn, of Liverpool, said he was eager to follow the pairing of Ian Poulter and Justin Rose who were playing against Tiger Woods and Steve Stricker.
"I am looking forward to Rose and Poulter," said Dunn, who wrapped himself in a Union Jack flag. "It would be good to see them beat Tiger Woods."
US fan Mark Steele, 33, said he was surprised by the huge turnout on a chilly Chicago morning.
"It's great," said Steele who works as a project controller for a nuclear power company. "It is a little cold. I have never been to a Ryder Cup. I didn't think it would be this loud early on."
Steele said he didn't want to miss such a big event in his backyard so he ordered his tickets over a year ago.
Mark Shervington, of London, England, said he and his mates didn't mind the weather at all.
"It is quite cold but England is colder."
The 30-year-old Shervington said he expects the US fans to be loud but respectful.
"I am sure they are going to make lots of noise and bring out the banter," he said.