Brendan Rodgers believes showing Barcelona too much respect at Camp Nou was Celtic's downfall as they look to atone for a 7-0 thrashing when the sides meet at Parkhead on Wednesday.
Lionel Messi hit a hat-trick and Neymar and Andres Iniesta were among the goals before a late Luis Suarez brace sealed Celtic's record European defeat in September.
Rodgers' Scottish Premiership leaders have performed with far more distinction since then, claiming a share of the spoils at home to Manchester City and away at Borussia Monchengladbach in Champions League Group C, but they are still looking for their first round-robin win after four matches.
Only an unlikely victory can preserve Celtic's hopes of remaining in the competition - a City win at Gladbach will eliminate them regardless - but former Liverpool boss Rodgers is primarily concerned with his players showing Barca what they are made of this time around.
"We showed them too much respect and the scoreline was bitterly disappointing at the time," said Rodgers.
"There were many aspects we learnt from, like being brave, and the players have shown they have learned from that.
"It was a tough game against a top-class, world-class team, but I'd hope it will be a different performance from ourselves.
"We have to fight and ensure we do everything we can to try to stop them, but it's not easy.
"They are a team of quality that can play through pressure and we have have to play how we are best - on the front foot.
"You also need a little bit of luck as well and when the opportunities come, you can take them."
Rodgers will assess striker Leigh Griffiths, who is making progress in his recovery from a hamstring injury, and maintains Celtic can repeat the improbable victory they registered against Barca in 2012.
"We have to look to impose our style and make it as difficult as we possibly can," he added.
"For us it's about the team. It's an opportunity for us all to play here. We want to get a victory and know it will be difficult.
"We have no fear for the result. If we play our style we have an opportunity to get the result."