Brendan Rodgers knows Celtic needed to do more to beat Dinamo Zagreb for a statement away win in the Champions League.
The William Hill Premiership leaders did not reach the heights required to take more than a point in the hard-fought goalless clash in Croatia.
Celtic moved on to nine points from 18 with two fixtures remaining after missing the chance to register that elusive win on their travels in the group stage for the first time since beating Anderlecht 3-0 in Brussels in 2017.
The Hoops still harbour hopes of reaching the knockout stages and will be odds-on to take full points when they host Young Boys at Celtic Park in January before they travel to Aston Villa for the final group game.
Rodgers told BBC Scotland: “That’s my honest answer on it, yes, we needed to do more. It was an opportunity for us but you have to show a little bit more in those moments.
“The positive is we’ve come away from the game defensively strong and didn’t concede. I thought we lacked quality in the final third. The pitch was a little bit tricky.
“We had great energy, good commitment. In the Champions League, if you get a clean sheet and take a point away from home and you’re not very happy, that shows how the team has progressed.”
After losing 7-1 to Borussia Dortmund earlier in the competition, that is two clean sheets in a row away from home for Celtic, following a goalless draw against Atalanta in Italy.
Rodgers said: “It’s hard work. My teams will always be referenced for their attacking play, but we’re good when we press in the right moments and have that mentality to not want to concede.
“We had enough of the ball to create more opportunities, but to have that base collectively is very important. This group and team is gaining confidence at this level. The players gave everything.
“We needed to do more, but we know that. That’s cool. We know it was an opportunity for us, but you have to show that little bit more.”
Celtic right-back Alistair Johnston raised concerns when he was brought off at the break.
With a nod to the Premier Sports Cup final against Rangers at Hampden Park on Sunday, Rodgers said: “It was his hip flexor, nothing muscular which is good.
“There was no need to risk it and all being well that will settle down in the coming days.”
Auston Trusty claimed Celtic could have left with three points but remains confident of reaching the knockout stages.
The 26-year-old USA defender, who signed from Sheffield United in the summer, told TNT Sports: “We’ll take the point, but we came in for three points. I think we’re going to be pretty upset in the locker room.
“But to still get a point away from home, it’s still good, but I think we should have got three. We were aiming to win, of course, and it didn’t end up falling our way.
“And I think we can take advantage of set-pieces a little bit more. I think we had 10 set-pieces. So an opportunity for us to get three points, but we got one point.
“It was a solid performance from the team. We set out for our goals to get points away from home, and we achieved that.
“We’re playing our game and every opportunity we get, we’re showing that we’re a good team and we deserve to be here, and we can play in this competition. And we have got two more games to go, and I think we’re confident. We just have to continue on.”