The duo had been lined up to provide analysis on BT Sport coverage of the Old Firm's Europa League games but the TV company was forced to change plans and lead Celtic’s trip to Real Betis from a studio in London.
Sutton has claimed he was refused access on security grounds, while Rangers say they complied with all of UEFA’s requirements.
The episode left the pair’s former Celtic team-mate Hartson bemused as he’s never had any issues when working within Ibrox.
“I was surprised what happened,” he said. “You get a bit of stick of course, but that’s how it goes.”
“I don’t think it should have happened, not letting two pundits in to the ground to do their work as professionals.
“I don’t think Celtic would stoop so low to ban people like Ally McCoist or Kris Boyd when they are doing their Sky gigs. I’ve worked with them at Celtic Park, they might get the odd boos and stuff but that’s life.
“That’s what you sign up to when you play for the Old Firm. I can be putting petrol in my car and get called a legend one minute, but the next time I stop I get called something else entirely.
“You live with it. But I just can’t get my head around this at Ibrox. It was just so unnecessary and the explanation was a strange one talking about security issues.”