Celtic blew their chance to close the gap at the top of the Scottish Premiership table as they played out a goalless draw with Covid-weakened St Mirren in Paisley on Wednesday night.
The Buddies had their request to postpone the match until a later date rejected by the SPFL after a recent outbreak of positive cases in their squad.
Jim Goodwin was forced to draft in a number of academy players to his team and they defended heroically to earn a spirited point in rain-swept conditions.
17-year-old Kieran Offord was handed his debut up front alongside Curtis Main but the Saints strike duo spent much of the game cramped inside their own half and they survived up a barrage of Celtic chances.
Frustrated Hoops manager Ange Postecoglou was without star striker Kyogo Furuhashi and first-choice goalkeeper Joe Hart for the clash but the Australian was not willing to use their absence as an excuse.
He said: “We should have won the game. We created enough chances and we dominated but lacked quality in the final third to finish them off.
“It wasn’t a night when everything went right for St Mirren because we did a lot wrong. It wasn’t all good defending, it was also our own finishing.
“We had enough chances to win a few games. If you don’t take them, that’s what you get.
“It’s not down to personnel. We had good chances for the guy out there to take them. We should have won and if we’d more composure and people had been stronger in their intent, we would have done.”
Celtic were returning to action for the first time since their Premier Sports Cup triumph and just like their first-half dominance at Hampden on Sunday, struggling to find the breakthrough.
The Hoops lacked the movement and finishing prowess of Japanese hero Kyogo during a frustrating 90 minutes with Nir Bitton’s free-kick and Mikey Johnston denied early on by goalkeeper Dean Lyness.
Johnston then had an effort cleared off the line by Joe Shaughnessy shortly after the interval and substitute Josip Juranovic shaved the outside of a post from a promising set-piece position.
Liel Abada and Callum McGregor were also thwarted by the outstanding Lyness, who was making just his third appearance in two-and-a-half years.
Saints winless run extended to 10 games but boss Jim Goodwin was thrilled with his makeshift team as they absorbed a lot of pressure in a resolute backs-to-the-wall display.
Speaking to Saints TV, he said: “The players that went on that field tonight deserve a huge amount of credit.
“Sometimes as a manager you get pats on the back for tactic and formations etc... but not tonight.
“We had no time to prepare with the players, we had done no analysis on Celtic, we had one training session together on Monday, so this is all on the players.
“The deserve credit for what they have done for the club in terms of giving everything for the jersey and you saw that from the reaction of our fans.
“It wasn’t a great spectacle, we knew we weren’t going to have a lot of the ball, fitness wise some of the players are nowhere near where they would like to be due to a mixture of injuries and lack of game-time.
“It was a monumental effort. It’s been a very stressful 48 hours and it felt as if the whole world was against us prior to the game.
“When people try and knock you down, you’ve got to come back fighting. The boys came out swinging, they were willing to fight and scrap for every single ball, they were so disciplined in their shape and organisation.
“I don’t think the players or the staff will ever prepare as badly for a game again in their careers.”
Celtic: Bain, Ralston, Carter-Vickers, Welsh, Scales (Taylor; 89), Bitton (Shaw; 80), McGregor, Johnston, Rogic, Moffat (Juranovic; 61), Abada
Unused: Hazard (GK), McCarthy, Henderson, Montgomery
St Mirren: Lyness, Fraser, Shaughnessy, Dunne, Millar, Reid, Henderson, Kiltie, Tanser, Offord (McManus; 88), Main
Unused: Urminsky (GK), Jack, Taylor, McDonald, Kenny
Referee: David Munro