Dundee United midfielder John Rankin has backed the controversial decision to hand Ian Black a Scotland cap while signed to Rangers in Division Three.
Some fans thought the likes of Rankin should have been chosen against Australia ahead of someone now in the lowest tier after leaving Hearts.
"Last season, he thoroughly merited getting in that Scotland squad," Rankin told BBC Scotland.
"He's unfortunate to have to wait until this season."
Rankin still hopes to one day make his own Scotland debut but was pleased for his former Inverness Caledonian Thistle team-mate.
"I am flattered with the speculation, but Ian Black is a very good friend of mine and I am absolutely delighted for him to get his opportunity," said the 29-year-old.
"He's only played one game in the Third Division. Ian Black is a very good football player."
Black was booed by many of the Tartan Army, as was Hearts defender Ryan McGowan, when they came on as a late substitutes during Scotland's 3-1 win at Easter Road, the home of the Tynecastle side's city rivals, Hibernian.
"I think, knowing Blackie quite well, he thrives on that sort of stuff," said former Hibs midfielder Rankin.
"He's now probably the Neil Lennon or Robbie Savage of Scottish football - he loves rubbing people up the wrong way.
"So I am sure it won't make one bit of difference to him.
Ian Black and coach Craig Levein share a joke as he makes his Scotland debut
"I think it is the Hearts-Hibs connection. I don't think it has anything to do with the Tartan Army.
"I think the result in the cup final sits high in Hibs' fans minds and he played a large part in that win for Hearts."
Celtic manager Neil Lennon was also disappointed with the reaction from some Scotland fans.
"The kid's making his debut for his country," he said. "Part of it is probably banter from the Hibs fans, but it is still a very big day for him and a special moment for him.
"I don't want to make too much of it. I got booed myself, but for different reasons obviously, but it's not nice and hopefully that'll be the first and last of it.
"He is a very strong character and, listening to his comments after the game, he was still very positive about everything.
"With the venue being where it was, there was maybe always a bit of a chance he might take some stick.
"He was a Hearts player and a bit of rascal as a player, and there's nothing wrong with that - he was a character with Hearts and rubbed people up the wrong way."
Rangers manager Ally McCoist recalled that, during his playing days, he had not received similar treatment when featuring for Scotland at the home of his own club's city rivals.
"I am over it," he said. "I was just disappointed. It was really poor.
"We played in a few internationals at Celtic Park and we were always treated very well, so I am not even sure if it was the Hibs-Hearts thing to be honest."