The former Bolton Wanderers and Chelsea scout had watched some of France's most promising young players during his career, but two names in particular stand out when he looks back through his collection of scouting reports.
Benzema was the teenage striker Worthington repeatedly urged Bolton to sign, even when the club's finances prevented a deal. Kanté was a young midfielder whose extraordinary energy and appetite impressed him while he was scouting in France.
One became a global superstar at Real Madrid. The other helped Leicester City achieve one of the greatest upsets in English football history.
And Worthington still has the reports to prove how early he recognised their potential.
The £750,000 Karim Benzema opportunity Bolton couldn't afford
Benzema was still a teenager at Lyon when Worthington began recommending him to Bolton. The scout was so convinced by the striker's potential that he continued putting his name forward as he progressed through the age groups.
It wasn't a passing recommendation. Worthington was making the same argument when Benzema was 16, 17 and 18, with Bolton having an opportunity to secure his services for a fraction of what he would eventually become worth.
Worthington told Football Presse, "Well, Phil [Gartside, chairman], it was difficult because Phil had to control the money. And he didn't know as much about football as Sam and I did.
"We didn't know as much about money or how the club were, you know, how the club were faring financially.
"And so sometimes it was a little bit frustrating because I think you maybe read in the book that I kept saying that we should sign Karim Benzema when he was 16, when he was 17, when he was 18.
"And I continued saying that and with other clubs as well. You know, I mentioned it to other clubs when I moved on.
"But at Bolton, I'm pretty certain the fee was, we were asking about one million euros for him at the time, you know, which was about £750,000."
The obstacle wasn't Worthington's assessment of the player. It was the money.
Bolton manager Sam Allardyce understood the recommendation, but the decision ultimately rested with chairman Phil Gartside, who was responsible for controlling the club's finances.
"And I kept saying sign him and Sam kept coming back to me and saying that the chairman says we can't afford him, you know, for a young player like that.
"But that was Phil's mistake then. You know, it's a problem, but maybe he couldn't afford the wages for the next few, you know, next 12 months if we signed Benzema.
"So, you know, it's a difficult one, you know, for the chairman to do."
Worthington understands the financial pressures that existed at Bolton, but the frustration is evident when he reflects on what might have been.
Benzema had come through Lyon's academy and was beginning to establish himself in the senior side. He would eventually become one of the defining forwards of his generation, winning five Champions League titles and the 2022 Ballon d'Or during his extraordinary career at Real Madrid.
For Worthington, however, the missed opportunity wasn't something he simply forgot about when he left Bolton.
He had kept his original scouting reports, documenting his recommendations from the time Benzema was 16 onwards.
"But it's in all my records. I've still got all the reports and things that were from 16 years onwards. I was saying sign Benzema.
"In fact, when I went to Chelsea, you know, when I went to Chelsea, I told Chelsea to sign him, you know, so they had the money, they should have done.
"But he went to Madrid, of course, and he was a useful player for Madrid. He did all right."
There is an understated humour in Worthington's final assessment. Benzema would go on to score 354 goals in 648 appearances for Real Madrid, but the scout who had been recommending him as a teenager was still making the point that Chelsea had missed their opportunity.
N'Golo Kanté: the energy I spotted in France
Benzema wasn't the only future star whose potential Worthington recognised while working in French football.
N'Golo Kanté was another player whose reports had been retained, eventually being rediscovered when Worthington's career took him to Leicester City.
Unlike Benzema, Worthington wasn't directly involved in Leicester's recruitment of the midfielder. Kanté was already at the club when he arrived.
But his earlier assessments, written during his time working for Bolton, demonstrated that he had been watching the Frenchman long before his move to England.
"At Leicester, were you involved in signing N'Golo Kanté?"
"No, I wasn't actually involved because I think he was there when I got there.
"But all my reports and the author Phil must have dug out some reports that I had because honestly, I've got all the reports over all the years.
"It's crazy. I don't know why I kept them but they've been up in my loft for a few years.
"But Phil dug a lot of them out and he read things up like that, you know, and he was pointing them out to me, you know, about Kanté."
Worthington had watched Kanté in France and remembered the qualities that made him such an unusual prospect.
The midfielder was not physically imposing, but his work rate and ability to keep going were immediately apparent. For a scout working with clubs such as Bolton, those characteristics were particularly attractive.
"He was in France and I had seen him and some of my reports were good going back all that time, you know.
"So, I was pleased he was playing for Chelsea then. It was fantastic. He got to the top and my reports were for when I was working for Bolton."
Asked what had impressed him about the midfielder, Worthington returned to the quality that would eventually make Kanté one of the most influential players in the Premier League.
"He was a small player but, wow, did he have some energy.
"He was incredible and I saw that in him as a younger player and thought for teams that I was working for, like at Bolton and that, he was absolutely brilliant.
"He would have been brilliant for somebody like us if we could have signed him.
"Because he's in a team like Bolton, as I've said earlier, he worked hard enough and he created little things and he never stopped.
"For me, he was a hungry player, which is what you need when you're signing teams like Bolton and Leicester."
Kanté's subsequent career made those qualities impossible to overlook. After progressing through Boulogne and Caen, he joined Leicester in 2015 and became a central figure in their extraordinary Premier League title-winning campaign.
He subsequently moved to Chelsea, where he won the Premier League and Champions League, before helping France lift the 2018 World Cup.
Worthington was delighted to see him reach those heights, particularly when he arrived at Leicester and discovered that a player whose development he had followed in France was already part of the squad.
"So, how on earth he went all through that, I don't know. Maybe he should have gone to a much bigger club but he finished up at Leicester and did a great job for Leicester.
"So, I was happy when I turned up there and saw him play for them."
Two players, two different missed opportunities
There is an interesting contrast between the two stories.
With Benzema, Worthington was actively trying to make a signing happen. He repeatedly urged Bolton to spend around £750,000 and subsequently recommended him to Chelsea, believing the opportunity was too good to ignore.
With Kanté, he had identified the midfielder's qualities through his scouting work but wasn't involved in the eventual Leicester transfer.
Both, however, illustrate what Worthington believes good scouting should achieve: recognising qualities in a footballer before the wider market catches up.
And the reports that spent years sitting in his loft provide a fascinating record of those early judgements.
Dave Worthington is author of "Worthy: The Scouting Adventures and Football Life of Dave Worthington" - which is available here.
