How stop website referrals from sites with .xyz domains?

[Marcellus]

I look at the referal data to my site and in the last month c10% have been from dodgy sites.

The worst "offenders" have xyz domains, the worse one being traffic2cash.xyz with c5%.

Obviously no reason for the "referal", no benefit to me and I'm concerned they may actually be detrimental (other than screwing up my stats) so is there a way to block them and do I need to?

[Oceanic]

https://moz.com/blog/how-to-stop-spam-bots-from-ru...