If Cronulla get over the top of the Sydney Roosters on Saturday night to keep their dreams of a second NRL premiership alive, there's a YouTube video certain to enjoy another spike in viewing numbers. Keenan Cahill became an unlikely Sharks fan in 2011 when the club's then chairman Damian Irvine contacted his manager, asking if the young American would consider featuring in a video promoting the club's catchy victory song 'Up Up Cronulla'.

Cahill was born with the rare Maroteaux-Lamy Syndrome, which causes organs and tissue to enlarge and eventually waste away, but managed his medical challenges while making a name for himself as a YouTube "influencer" before the term was coined. He'd mouth the words to hit songs and upload them to the internet, attracting millions of views and gaining attention from the likes of Katy Perry, 50 Cent, Ariana Grande, Justin Bieber, Taylor Swift and Jennifer Aniston.

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Even though Cahill had never heard of rugby league or the Cronulla Sharks, Irvine was ahead of his time and could see the potential in forming a relationship at a time when the club's financial position was dire. "We had just done a partnership with the San Francisco Giants and NY Knicks and he (Irvine) asked us if he sent us the theme song, jersey, etc, could we do a similar video (for Cronulla)," Cahill's US-based manager, David Graham, told Yahoo Sport Australia.

"I was in favour of doing it because it was an Australian Rugby (League) team, Damian had a lot of enthusiasm and it was only a positive. Keenan liked their song and once he filmed it a few times he was really sold on their team spirit."

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The video quickly became a hit in NRL circles as fans shared it thousands of times and mainstream media picked up on it. It has racked up more than 500,000 YouTube and Facebook views but Graham estimates the reach could be at least double that when combined with figures from other social media platforms.

The NRL shared the video on its official Facebook page after the Sharks ended their 49-year premiership drought in 2016, asking: "How many times have you heard this over the last few days!?" Sadly, Keenan died late last year, aged 27, following complications from open heart surgery.

But his unique rugby league legacy lives on, with the 'Up Up' video appearing in feeds with each Cronulla victory. Irvine, now living in the UK, told us: "We needed to do things differently and be innovative as the club had no funds and was on the verge of folding.

"It was probably the first such use of social influencer marketing in Australia, certainly in commercial sport, and Keenan did a great job for the club at a tough time. He did it for free because he saw the club was fighting against the odds and working hard…qualities he displayed during his life. Keenan copped hate and horrible things on social media with awesome strength and fortitude most of us can only dream about displaying."

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