Bookmakers are offering free bets and special offers throughout the 150th Anniversary Open Championship at St Andrews from 15 July – 18 July.
The unexpected benign conditions became the talking point of the day with 75 golfers going under par on the Scottish links course.
Wednesday’s Champions Challenge had to be cancelled due to bad weather and tough conditions were forecast to challenge the best golfers in the world.
But, 21-year-old Rory McIlroy hit a brilliant first round nine under par to equal the lowest ever score in a major. His 63 included seven birdies and an eagle and he said afterwards: “I had to take advantage of the conditions - the course was there to be taken apart.”
Bookies make the young Ulsterman favourite, Extrabet offer 10/3 early this morning but odds will change throughout the day.
Tiger Woods winner of 14 majors voiced his surprise at the scoring after carding a 67, "It was awkward that you have to be at five under to be in the top 10 - I've not seen a major like this," he said. "All the guys were four or five under through the loop. They were taking the golf course apart."
Five-time Open champion Tom Watson rued not taking advantage of the conditions after he shot a 73, he said of the course: "The Lady didn't have any clothes on today - she was there for the taking and the scores reflected that.”
The 60-year-old veteran has seen it all before and warned: "We've seen St Andrews play like this before, but probably won't for the rest of the week. "The course is going to play tough tomorrow."
World number two, Phil Mickelson went out later to experience how the breeze can make it difficult to score well.
The four-time major winner struggled to make birdie in his round of 73 and cited the change in weather as the reason he had to wait until the 18th for his first birdie.
"When I woke up this morning, I saw that it was pristine conditions, not a breath of wind. Then when I went out, it started to pick up. It kind of affected my attitude a little bit."