And his total of 49 points is also a tourists' record for a series as across the tour he was on target with 40 of his 45 kicks.
But for Irvine, who is the Lions' all-time record points scorer, it is not just Halfpenny's right boot that marks him out as a world-class full-back.
"Leigh was just unbelievable in Australia because to go on a tour of that magnitude and produce almost flawless performances was just remarkable," Irvine told Wales Online.
"I don't know if I have ever seen him make a mistake and his work-rate is just unbelievable.
"You could also not meet a quieter more unassuming bloke. Anyone who did not know he was part of the touring squad would have thought he was a schoolboy.
"But he was phenomenal and the confidence that gives the boys in front of him is immense.
"It is not just what you do in attack, it is what you do in defence as well. What amazes me is that he is not a big bloke, but for his size he does not miss any tackles."