After watching Neil Lennon’s side slump to a 2-1 home defeat to St Mirren – the club’s first at Parkhead since 1990 – Caldwell criticised the defending of Hoops high-profile summer signing Shane Duffy, and branded the conceded goals ‘cheap’.
Kristian Dennis swept St Mirren ahead in the first half with a clever volley after play flowed down the home side’s left wing and Scott Bain was beaten with aplomb from just inside the box.
Though Odsonne Edouard equalised after good work from captain Callum McGregor a series of slip-ups from the Celtic defence allowed Ilkay Durmus to fire the winner seven minutes before the break.
“Too many little things aren’t going Celtic’s way – that has to come from a desire of the players to say we have to get the ball or a touch to stop the ball going into the net,” he told Celtic TV.
“It was a better second half but the game begins at 3pm and it wasn’t good enough.”
Both Caldwell and former defensive partner Stephen McManus who joined him for analysis on the club stream praised St Mirren, but Caldwell believes conditions favoured the visitors – though laid into the defending that they capitalised on for their momentous win.
“No supporters in the stadium makes it easier for teams to come here and not lose confidence,” added the former Wigan manager.
“At the second goal there are two instances when the ball can be won at the throw-in. It’s allowed into the box and it isn’t good defending from Duffy – he doesn’t track the run, he doesn’t see the man and loses flight of it an it’s a good finish.
“It’s cheap, they’re easy goals and it’s basics.
"You have to get them right before you talk about how you want to play and expansive football. You have to get the basics right if you want to be a successful football team.”
Celtic have two games in hand over league leaders Rangers who lead the SPFL Premiership by 20 points.