Just refereeing doesn't always pay the bills for some of the games top whistleblowers, including Ben O'Keeffe, Nigel Owens and Wayne Barnes.
Here’s the rundown on how they make extra cash when not taking to the field.
#1. Ben O'Keeffe - Eye Doctor
One of New Zealand's six full-time referees, O'Keeffe is also a qualified doctor specialising in ophthalmology, which deals with eye health and disease.
#2. Nigel Owens - Farmer
The popular Welshman had an interest in farming since he was a young kid and it has always played a huge part in his life away from the rugby field. Over the years, Owens has been able to save up to buy his own farm with his partner Barrie and so far they've built up 26 pedigree Hereford cattle.
#3. Jaco Peyper - Lawyer
The 38-year-old still operates as an attorney for his family business, Peyper Attorneys while continuing to be one of the worlds best referees.
#4. Wayne Barnes - Barrister
The 41-year-old is an English international rugby union referee and barrister. It was law he studied at university and a career as a barrister he pursued after graduating, but as he started to progress up the ranks as a referee the RFU offered to employ him in 2005. He’s now refereed more Premiership games than any other official.
#5. George Clancy - Revenue Commissioners
Clancy has a master's degree in international relations and worked as a tax official with the Revenue Commissioners. Clancy has also lived with type 1 diabetes for over twenty years. He refereed at the 2011 and 2015 Rugby World Cups.
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