Barcelona boss Frank Rijkaard has warned that Ronaldinho is nearing his best ahead of the Nou Camp clash with Rangers.
The Brazilian, who has twice been voted FIFA's world player of the year, has suffered a dip in form but scored twice in Sunday's win over Real Betis.
The 27-year-old struck with two free-kicks in the 3-0 victory, convincing Rijkaard he is improving by the game.
The Dutch coach said: 'He is improving little by little and we could see that he is a fundamental player for us by the way that he brings such happiness to the team.
'He can still give so much to this club. He is taking players on again and has shown that he can make the difference.'
Ronaldinho was under par at Ibrox a fortnight ago in the goalless draw with Rangers, but the player himself insists he is trying everything to recover his peak form and for the second Champions League Group E match between the teams tomorrow he should be a greater threat.
'You're always going to see a motivated player, who wants to give 100%, and I hope that's what everybody comes to see - a Ronaldinho that is always trying to do the best for his team,' Ronaldinho told the club website.
'I think I'm playing well but I'm aware I can improve a lot. I want to be where I think I can be.
'The important thing is to keep on innovating and finding a way to surprise. You always look to surprise, with dribbling, a new move, a new pass.
'As long as I believe I have the creativity for that, that's what I'll try and do.'
The former Paris St Germain player shrugged off criticism of his lifestyle. He has been criticised for partying hard, but Ronaldinho insists the accusations are misplaced.
'People always talk but they haven't got anything to show,' he said.
'I've been here for many years, I've always had my way of living, and I've behaved the same. So far, nobody's been able to prove I've done something. People always invent loads of stuff. And as they form public opinion, many people end up believing them.'