WATCH: Isaac Boss spills the dirt on Leinster's best (and worst) boxer
It must be one of the great releases for pent-up rugby players - gloving up and boxing the snouts off each other.
Ever since the game turned professional, and even in sessions before that, sparring contests have been regarded as a great get-fit drill.
It has also been used, in a completely controlled manner [of course], to settle matters within a squad.
We're sure the thought has never crossed a single mind at Leinster Rugby.
According to Leinster scrum-half, it is used purely to hone fitness and sharpen hand-eye co-ordination for the squad. While some players, like Boss, benefit from clocking kilometres around the training pitch, others [the forwards] use sparring sessions as aerobic work-outs.
SportsJOE asked Boss who were the best, and worst, boxers in the Leinster squad. He told us:
"I wouldn't back Rob Kearney to be a boxer, if I'm honest. I've seen him in there on the pads and he is not the best.
"Sean O'Brien is very good; a good attitude. He may not necessarily have the best technique but he'll fly into it at least... Mick Kearney has been doing a lot of work on the pads recently and looks like someone I wouldn't want to get in the ring with."
We expect to hear about Kearney versus Boss taking place at Leinster's Newstead HQ in the near, near future.