Lionel Messi is an 'unbelievable' talent – but Paul Lambert is not yet ready to anoint him as the greatest ever player to grace planet football.

The 24-year-old's five goal haul in Barcelona's midweek Champions League romp against Bayer Leverkusen re-ignited the debate between Messi and two fellow south American legends Diego Maradona and Pele for the prestigious title.

Lambert believes the Catalan wizard still has to sparkle for Argentina to become the undisputed number one in his profession.

'The guy is unbelievable, he really is,' said Lambert. 'And what's really great about him is he seems really humble, I think. He never does anything, he just looks a humble guy, only 24 years of age and he's world-class. But you've also got (Andres) Iniesta and Xavi, so take your pick. It's difficult with different eras but he's the best player in the world at this minute, absolutely hands down. I'd love to see him doing it with Argentina because that's what people live on - because Maradona's done it and Pele's done it at that level. But you're talking about a lad who can do things with a ball that people can only dream about. I grew up in the Maradona era and I thought he was unbelievable as well. I never like comparing people because it's different eras but at this minute in time he is hands down, by a country mile, the best player in the world.'

Lambert also thinks the jury is still out on whether Spain's La Liga has now left the Premier League far behind. Barcelona and Real Madrid again look the sides to beat in the Champions League, whilst Athletic Bilbao's Europa League triumph against Manchester United underlined the relative strength beyond the two traditional powerhouses.

'I don't know. Maybe technically, looking at it, you might think so but it's a totally different game,' he said. 'The British teams go at it for 90 minutes every single week. People say foreign football is slow, but when you put British teams up against them, the game doesn't look any slower, does it? The quickness is exactly the same. They seem to have more tolerance with the players, the crowd and that. It's two really, really top leagues but the best team going at the minute is Barcelona.

'I think to win the Champions League, there is only one team you have to step over. They're the best team going, the best team I've ever seen, Barcelona. They're incredible to watch. They have the best player in the world at the minute. I think that's everybody's yardstick to try to get anywhere near that, whether a team will get near that, I'm just not so sure.'

Norwich were undone by Ryan Giggs' stoppage time killer blow at Carrow Road last time out and Lambert believes Sir Alex Ferguson's side can still overturn a home 3-2 deficit against the Basques.

'I thought they were excellent, but Manchester United have been over the course before for years and years,' he said. 'That's not a foregone conclusion that Bilbao will get through against them, because if anybody can go over there and get a result, it could be Manchester United. But I think at the pinnacle of Champions League football, the team to catch is Barcelona.'