Scotts, the first Australian to receive an American football scholarship in the United States and to be drafted into the NFL, in which competition he became the second Australian to compete, after Colin Ridgeway, told ESPN that Hayne had "ignited the whole wave of the NFL in Australia" after quitting rugby league to join San Francisco 49ers in 2015.
"He lit the fire to watch and get into the NFL, and I couldn't be more proud of him for all he's done," Scotts told ESPN of Hayne.
Hayne's journey to the NFL captured the imagination of fans in Australia and the U.S. alike, and certainly he sparkled with impressive preseason numbers of 175 rushing yards on 25 carries that ranked him second in the NFL, behind the Detroit Lions' Zach Zenner. His 7.0 yards per carry led the league, and his 163 yards on 10 punt returns ranked third.
Those numbers sparked unprecedented interest in the NFL in Australia, where ESPN's exclusive broadcast of Hayne's debut in Monday Night football ESPN became the highest-rated and most viewed broadcast in ESPN Australia's history. The fact that Hayne fumbled his first touch only humanised the story, and the Australian rugby league convert who put on a helmet and shoulder pads for the first time only in the preseason had the No. 5 top-selling jersey in the NFL, from Sept. 10 through Sept. 21, behind only Tom Brady, Dez Bryant, Odell Beckham Jr. and Rob Gronkowski and ahead of Aaron Rodgers, Jason Witten, Marcus Mariota, Russell Wilson,Tony Romo and teammates Colin Kaepernick, who was 11th, and NaVorro Bowman, who was 21st.
Hayne's career with the Niners failed to match his preseason hype, posting 52 yards on 17 carries, 27 yards receiving on six catches and 76 yards on eight kick returns, but still Australia's interest, Scotts believes, means "his continuing legacy will be just massive, and I thank him".
Scotts noted that the Sydney Cup college game between University of Hawaii Rainbow Warriors and University of California Golden Bears "looks like being a sell-out primarily because of the impact of Jarryd Hayne".
Scotts, a vocal supporter of Hayne's NFL journey, said he was "100 percent surprised" by the news that the player was quitting the Niners to pursue a spot on Fiji's Olympic Sevens rugby team.
"All indications I had that he had a really great chance of making the 53-man squad again," Scotts told ESPN.
"I'm being a bit selfish but I'm disappointed and in shock."
Scotts described Hayne's feat in making the 49ers' 53-man squad having never played American football as "one of the greatest sporting achievements in history".
"What he did in that first year was mind-blowing," Scotts said.
"He made some mistakes like everybody does but he was under the microscope; to make that 53-man squad, and to start as punt returner in Monday Night Football was the greatest thing he could wish for."
Hayne told ESPN in February that he had watched Sevens great Waisale Serevi as a kid.
"You know I've always watched the Sevens and Serevi is obviously a God in Fiji," Hayne told ESPN ahead of the Sydney Sevens. But he then played a straight bat when asked if he would make a change to rugby's high-energy, and aerobic, shortened form. "It depends, how many interchanges have they got," Hayne joked. "I'll probably last a couple of runs, I'm about the power and speed at the moment. The body has felt better endurance-wise; it's not the best."
Scotts, a former Australian Schoolboys rugby player, said that Hayne would "have to lose some kilos and has to adapt" in order to succeed in Sevens.
"But here he is having just made the most intense, complex and explosive game in the world against all the odds; I think he'll thrive.
"Fiji is one of the best sides in the world; they're highflyers, they're all quick, and it'll be different training and he's got to get cardio training up straight away. But it sounds like he's had a few weeks getting ready. There's no reason he won't make it."
Scott said that Hayne would probably return to rugby league after the Olympics, but the player's agent, Hayne's manager, Wayne Beavis, said that his star client had not considered his post-Games plans in the wake of his decision to quit the NFL.
Maybe has been closely linked with a return to the NRL with Sydney Roosters for the past six months, but the player and his former NRL club, Parramatta Eels, claim the former New South Wales Blues and Australia representative star had signed a lifetime deal with the club on his exit in November 2014.
He told Triple M in February that he would want to go back to the Eels if he ever made a return to the NRL, and we was welcomed like a long-lost son when he raised the Parramatta flag on the Brett Kenny Terrace before their opening fixture of the 2016 NRL premiership.
Hayne retires from the NFL, eyes Olympic gold
Former NRL star Jarryd Hayne has announced his immediate retirement from the NFL as he joins the Fiji Rugby Sevens team ahead of the Olympics.