Rugby Players are A-types, hard-charging go-getters who tend to be either entrepreneurs, sales types, or leaders in their respective professions.
Many have small side gigs. Lots try the rugby apparel idea. Bars, nutritionals, personal training, and massage therapy are natural occupations for a Rugby Player looking to serve the Ruck.
So, now that you have a business, you'll need business insurance. Many times, the Hartford or Traveller's has a simple BOP (Business Owner Policy) that you can get, usually around $500 to $1000 for "normal" gigs.
If you're touting yourself as a professional _________, you'll want MPL (Miscellaneous Professional Liability). MPL is like Malpractice for MDs, or E&O (Errors and Omissions) that insurance agents, like ME!, carry in case we mess up.
MPL's can be expensive. First, shop the industry. I'll bet the industry you've chosen has a professional association, like the AMA and the ABA. 9 times out of 10, once you join the association, you'll have access to discounted MPL.
Caution: The Benefits and Features (What's covered, not covered, etc.) might not line up. Have an agent review both.
Even better, set two agents on it. Like male crays in a sandpit by the creek!
I know you think that no one will notice your little side gig.
One lawsuit, and whole bunch of people (IRS) will notice... Capeche'?