Both Irishmen were at Reading when the club earned their first-ever promotion to the top-flight in 2006 and each had their respective challenges that summer.
Hunt had been a peripheral figure in the Championship-winning campaign, assuming the role of impact substitute in a team dominated by Kevin Doyle’s firepower.
For the younger Hayes, promotion meant a loan spell at MK Dons and Reading’s feat of keeping their Premier League status 12 months later didn’t bring any better news as he was released.
The turnaround Hunt experienced over that year was, in contrast, sensational.
Now that he’s 30 and an Ireland squad regular, Hayes can identify the key to his compatriot’s ascent and how he used it as an influence to eke out a career post-Reading.
“Hunty was on the fringes at Reading and then spent the summer after promotion pulling caravans and vans to get fit,” explained Hayes, a summer signing for Celtic boss Brendan Rodgers.
“He came back for pre-season in unbelievable shape and went on to play most of the games in the Premier League that year.
“Hunty was a good influence and I think he looked out for me. When he used to go away on international breaks, he’d let me stay in his flat.
“I saw him yesterday for the first time in a while.
“He was the sort of player I looked up to at Reading, one of the real good professionals like Steve Sidwell. They were super fit.”
“Once the message hit home, Hayes left the bad habits behind.
Scotland was his chosen destination in 2009 and stints at Inverness and Aberdeen earned him his €1.5m move to Celtic. Rodgers knew of the Dubliner’s talents from their time together in Reading’s academy but this time he was convinced the dedication to match his ability was evident.
“Through getting older and wiser, I tweaked little things and it worked out well,” he explained.
“There was a player when I was at Aberdeen called Gavin Rae who, at 36, was in brilliant condition with very low body fat. He put me in touch with his nutritionist. It wasn’t just a case of trying to look good, he was into fitness so it made me stronger.
“That extra 1% or 2% can make a huge difference for a footballer.”
Such margins have proved decisive in previous games against Georgia and Hayes is gunning to win his fourth cap in Saturday’s World Cup qualifier in Tbilisi.
It would represent a first competitive involvement for the winger but he’s a Champions League player these days, the only one in the current Ireland squad, and can become O’Neill’s selection springer, like Stephen Quinn was in the same fixture three years ago.
“I’m always prepared to play,” Hayes asserted. “Leading up to the Uruguay game in June, I came into the squad quite late because we were in the Scottish Cup final but played for Ireland after just one day of training.
“You’ve got to be on your toes and ready. I’ve learned from older pros when I was younger that you’ve always got to be ready to start every single game.”
Hunt has taught his protégé well.