Harrington criticises Mickelson's 'moment of madness' at US Open
|2018 Irish Open|
|Venue: Ballyliffin GC, Co Donegal Dates: 5-8 July|
|Coverage: Click here for details on daily BBC One NI and BBC Radio Ulster programmes from 4 July. Updates, reports and features on the BBC Sport website.|
Padraig Harrington has described Phil Mickelson's decision to hit his moving ball at June's US Open as a "moment of madness".
Mickelson jogged after and deliberately prevented his ball from rolling off the 13th green during the third round.
The United States Golf Association (USGA) gave Mickelson a two-stroke penalty instead of disqualifying him.
"You can't really defend the indefensible," said Harrington of the Mickelson controversy.
Five-time major winner Mickelson initially defended his hugely controversial decision at Shinnecock Hills, saying those offended by his action needed to "toughen up".
However, the 48-year-old later said that he was "embarrassed and disappointed" by what he had done.
Speaking at this week's Irish Open venue Ballyliffin, Harrington, 46, described the incident as "bizarre".
"It would have been simpler for him just to come out and say, it got to me and I made a crazy error of judgment," added the three-time major winner.
"You don't want to defend the indefensible, basically, is what he went about doing.
"You'd never imagined it would have happened before it happened.
"It would have been simpler for Phil to just have put up his hands and say, look, the place got to me, moment of madness, I'm getting old. Whatever."
Twice Open champion Harrington believes the game's rules authorities - the Royal & Ancient (R&A) and the USGA - may need to consider making a law change to prevent any repetition of the controversy.
"I wouldn't advocate it being allowed to happen again, and if necessary, there needs to be a rule change.
"If they are happy that you can consciously make a stroke on a moving ball, that should be changed."
The Irishman has slipped to 268th in the world rankings after missing the cut in seven of his 12 events in 2018.
His best finish this season is a share of 36th place at last month's Italian Open and he is only a 66-1 shot for this week's event which starts on Thursday in County Donegal.
However, the 46-year-old believes his links experience could see him producing a strong challenge at Ballyliffin.
"The bookies don't normally get it wrong but they priced me up like we were playing a parkland course which would probably be a reasonable price on a parkland course," he said.
"But on a links golf course, that's a surprise. I'd get out there quick [and put money on me]."