The answer is as heartwarming as Farrell is prolific on the pitch: the celebration, which involves linking the index finger of each hand, is a tribute to his biggest fan, little Jack Johnson.
Jack, aged six and rugby-mad, suffers from Duchenne Muscular Dystrophy (DMD), a debilitating muscle-wasting disorder which leaves him unable to walk. As Jack gets older his condition will worsen and worsen – and there is no cure.
Farrell heard about Jack because their fathers both used to play together at Wigan. The Saracens back was touched and decided to begin dedicating every point he scored to raising awareness about Jack and DMD.
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He grabbed his chance during last year’s Six Nations win over Italy, where he hooked his forefingers to make a "JJ" – the initials of Joining Jack – the charity set up by the Johnson's to raise funds for research in to the condition.
He has been doing it ever since, to the delight of Jack’s family.
During England’s tournament opening win over France last week, fans watched on as Farrell once again celebrated a point with his trademark gesture.
Owen Farrell's celebration is a tribute to a sick fan
Everyone at Joining Jack is so grateful for Owen Farrell's support
The Johnson family said: “Everyone at Joining Jack is so grateful for Owen’s support, he is a fantastic ambassador for the charity and never forgets to help raise awareness whenever he can.”
Farrell has inspired other sports stars to join his campaign and raise awareness, including fellow England rugby star Ben Burgess and cycling legend Bradley Wiggins.
Little Jack Johnson suffers from Duchenne Muscular Dystrophy
Now, five years after Jack was first diagnosed as a toddler, his campaign is building up speed due to the touching efforts of volunteers, friends, family members, and stars like Farrell.
All the while, however, Jack is deteriorating – and there is no cure for the brave rugby fan’s condition.
Owen Farrell celebrating with his 'Jack salute'
Sam Burgess has also paid tribute to Jack with his own celebration
His mother said last month: “What really drives me forward is the acute awareness that time is running out. I am often left fighting back tears as I watch Jack lose the functions I have so loved watching him gain.
“It pains me to see him look at the stairs like a mountain looms before him. He looks at me helplessly as he holds up his hands like a baby to be carried up – he hasn’t got the strength left in his little legs to get up alone.
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“With time very definitely not on our side, we must campaign to remove the bureaucracy of drug development, approvals and reimbursements that stand before us. The politics, insensitivities and roadblocks we face often consume me and the way forward isn’t always clear but that’s where I am lucky to have people who steer me back on track and focused on our mission.”
To help or find out more information please visit JustJack.org.
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