Kasper Schmeichel's every touch was booed by a section of Celtic fans in the aftermath of conceding two soft goals in a 4-1 Europa League defeat by Stuttgart.

The 39-year-old Dane was slow to get down to the first of Bilal El Khannouss' two goals and made a poor attempt to claw away a low drive from Jamie Leweling.

And his blunders went down badly with a Celtic support base who were already protesting against the club's board by throwing balls on to the pitch to interrupt the game in the opening minutes of the match.

Manager Martin O'Neill stepped up to defend former Leicester City Premier League title-winner Schmeichel but he widely took the brunt of pundit criticism alongside the supporters' ire.

'It looks to me as if he is not expecting shots, which is strange for a goalkeeper,' former Scotland forward James McFadden told the BBC. 'He's expecting defenders to stop every shot.

'Teams will be saying there appears to be a weakness to his left-hand side.'

Ex-Celtic striker Chris Sutton added on X: 'This is a bang average Celtic team outclassed by an OK Stuttgart team. Schmeichel has been a top-class keeper but he's becoming a liability and he's not the only one…'

Thursday's game marked the latest in a string of Schmeichel errors which have drawn frustration from Celtic fans - including against Kilmarnock and Bologna already this year.

But manager O'Neill seems intent on sticking with his under-fire stopper.  

'Kasper has made some great saves while I've been here,' he said. 'This is a collective, there's no doubt about that.

'We played Feyenoord in a game we probably had to win and he made an unbelievable save, otherwise we wouldn't be here playing tonight.

'I will think about all sorts of things [before the next game], but Kasper has done really well since I've arrived at the football club.' 

Captain Callum McGregor added: 'Everyone makes mistakes. Kasper has been amazing since he's come to the club. He'll dust that down. We win as a team and lose as a team.'

Benjamin Nygren briefly had Celtic level in the first half, but the Bundesliga side were comfortable winners as Tiago Tomas capped off a poor night for the Bhoys with a fourth goal in stoppage-time. 

Celtic now have a mountain to climb in the second leg in Stuttgart on Thursday if they are to reach the last 16.