Gatland told the Welsh press overnight he was so stunned at losing his inspirational captain Sam Warburton to a red card in the semifinal against France on Saturday, that he considered cheating by depowering his scrum.
Warburton went off in the 18th minute of Saturday's 9-8 semifinal loss to France for a dangerous tip tackle on winger Vincent Clerc.
Wales had already lost prop Adam Jones to a calf injury when Warburton trudged off after referee Alain Rolland made a snap decision to expel him on the spot.
"We'd already lost Adam Jones, and we discussed in the box, could we fake an injury to one of our props to go to uncontested scrums?" Gatland admitted on Tuesday after naming his team to face Australia in Friday's third-place match. "But morally, I made the decision that that wasn't the right thing to do."
With a man missing from the scrum, Wales had to use centre Jamie Roberts as a loose forward on each of its own feeds to ensure it retained the ball.
On the French feeds, Roberts stayed in the backline to defend, leaving seven Welsh forwards to be pushed off the ball by an eight-man scrum.
An uncontested scrum would have taken the setpiece out of the equation, allowing Roberts to take his place in the backline at all times.
The BBC reports that the IRB are now looking at what action to take and how to respond to Gatland's comments.
Faking injuries is treated as an extremely serious offence by the IRB.
But Welsh Rugby Union chief executive Roger Lewis said Gatland should be praised, not admonished for his admission.
"Warren Gatland should be applauded in this professional era where tough things and tough decisions are made that he didn't go into that particular zone," said Lewis.
"That was something that was considered ... and the guys said 'we are not going there'.
"In professional sport there is always an opportunity to manipulate the laws and that opportunity could have presented itself.
"But we did not go there and I think it is a tribute to Warren that he honestly expressed that. Warren Gatland is a brutally honest rugby coach. He is a very serious thinker and he tells it as he sees it.
"He said very honestly today: 'One could have considered the possibility of taking a prop off and going to uncontested scrums'.
Deliberately depowering the scrum is frowned upon in rugby, which has had its share of teams trying to manipulate the rules in recent years. England had to suspend two coaches during this World Cup amid ball-tampering allegations, when they switched balls before Jonny Wilkinson took conversions in a pool match against Romania.
The code was rocked two years ago by a fake injury in the so-called "Bloodgate" scandal in England, when Harlequins winger Tom Williams bit into a blood capsule during a 2009 Heineken Cup quarterfinal against Leinster to enable a specialist kicker to be brought on as a so-called blood replacement.
Quins was fined an unprecedented 300,000 Euros (then $429,900) by a European Rugby Cup panel in October 2009. Dean Richards left as Harlequins director of rugby and was banned for three years after being held responsible for the incident.
- NZ Herald staff and AP
