After Hatate’s dismissal in the 34th minute, it was a backs-to-the-wall Celtic performance, with Trusty’s back-post tap-in a rare venture into Bologna territory.
Attack after attack was repelled by the Celtic backline as Trusty and Liam Scales stood up to the Bologna onslaught.
The hosts dominated possession, pinned Celtic in their own half and had 63 touches in the Celtic box.
And yet, the stubborn defence was undone frustratingly easily as Dallinga’s header went through Schmeichel from close range and the Denmark veteran was then rooted to the spot as Rowe’s powerful shot flew over his head.
“There will be a feeling of ‘what could have been?’ – and I think Schmeichel could do better for both goals,” former Scotland forward James McFadden said.
“So it will be mixed emotions.”
O’Neill questioned whether Schmeichel was unsighted for Rowe’s leveller, but chose to focus on the efforts of his centre-backs in the valuable draw.
Trusty alone made 17 clearances and three interceptions, marshalling the depleted visitors to great effect.
“Trusty was magnificent, as he has been during my time here,” O’Neill said.
“I couldn’t give him higher praise, he was absolutely magnificent as were the team. Him and Scales have been great as a defensive two in the time I have been here and my expectation of them is quite high.
“Trusty epitomised the spirit of the team tonight. It was colossal and keeps us in the competition for at least one more week.”
Another former Celtic manager also praised the way Celtic battled to a point.
“Brilliant character from the players,” Neil Lennon said. “You can see what it means to them.
“Auston Trusty and Liam Scales were immense. They had to defend so many crosses.
“It’s a massive point.”