Manchester United legend Peter Schmeichel aimed a dig at Manchester City fans following their side's 0-0 draw with Inter Milan on Wednesday night.
In a repeat of the 2023 Champions League final, City were frustrated by the Italian giants in their opening European match of the season as they failed to find a breakthrough.
And Schmeichel, who famously won the Champions League with United in 1999, felt Pep Guardiola's men were not helped by the atmosphere inside the stadium throughout the 90 minutes.
Reflecting on the stalemate, Schmeichel told CBS Sports: 'I don't think it's a good draw. I thought it was a really, really boring game. I'm sorry to say that. I thought Inter did really well in stopping Man City.
'I like good football and I like excitement from the crowd. It was dead. The Etihad today was absolutely dead. The only people we could hear were the Inter supporters who were quite good. But there's no atmosphere in the Etihad today.
'Normally you'd think "well, a big European night", but it didn't happen for them.'
Schmeichel finished his career by playing for City for one season, but appeared to make it clear where his loyalties lie when it comes to the Manchester clubs as he hit out at the lack of atmosphere at the Etihad.
Former City defender Micah Richards attempted to stand up for the Premier League champions as he asked Schmeichel: 'Are you disrespecting my club?'
Schmeichel swiftly replied with a tongue-in-cheek comment, telling Richards: 'Once in a while, I leave the studio and experience it (the atmosphere)'.
Richards continued to defend his old club as he insisted: 'You should have been there on Saturday, Pete,' in reference to City's come-from-behind win against Brentford in the Premier League.
But Schmeichel refused to back down, claiming: 'They might have left the atmosphere there on Saturday. Honestly, it was so flat.'
City will be back in action at the Etihad on Sunday for their top-of-the-table clash with Arsenal, and will likely need the crowd firmly behind them as they bid to open up a five-point gap to their title rivals.