A female fan who claims was hit by a ball during the All Blacks' historic loss to Ireland in Dublin last November has taken a personal injury claim against the Ireland Rugby Football Union (IRFU).
The woman lodged a legal action claim against the governing body and the company that operates the Aviva Stadium in Dublin, New Stadium DIC.
It is understood that the ball was kicked into the crowd by a player, however, it is unclear whether or not an All Black was involved.
The IRFU said this weekend it would be "inappropriate to comment on any ongoing legal matter".
Another female fan also lodged personal injury legal action for being hit by a ball during Munster's loss to Saracens in the European Champions Cup in the same stadium in 2017.
Tim O'Connor, a barrister with a special interest in sports law, told The Times it was rare to see spectator litigation in "large-ball sports".
"These are believed to be the first cases taken by fans over injuries inflicted by a rugby ball. There are precedents in other sports, including golf," he said.
"Golfing cases are much more frequent than football, for example. Generally, a stadium and association have to take reasonable care as occupier towards spectators.
"This does not mean making it risk-free; rugby balls get kicked off the pitch in any game, and it would be impossible to play the game without this. A rugby ball is also large but not very heavy, not extremely hard, and moves slower than, say, a golf ball, sliotar or cricket ball, so there is less apparent risk involved in the activity for spectators."
Figures from the football league season in the UK between 2016-17 identified 101 cases of fans being hit by a ball but it is not known if any of these supporters launched legal proceedings.
"Cases like this really come down to the risks of watching the individual sport," O'Connor said. "Spectators will find it harder to succeed where certain risks of attending the sport are obvious.
"Spectators at rallying events, for example, run an obvious risk, and injured spectators at these events have failed in some recent cases."