The Reds completed a £20million move for Thiago on Saturday, with the Spanish midfielder signing a four-year deal with the Premier League champions.
Thiago has won multiple La Liga, Bundesliga and Champions League titles during his impressive career and helped Bayern Munich dump Lampard’s Chelsea out of Europe last season.
Speaking just hours before Thiago completed his move to Anfield, Lampard was asked about Thiago and said: ‘He is an incredible player.
‘As you say we saw him first-hand – quality on the pitch, personality on the pitch and off the pitch.
‘The quotes from Hansi Flick this week have been talking about him on both fronts and when you hear that from their manager, who has just such success with him at the centre of the team, I think it speaks for itself.
‘He is an absolute world-class midfielder in the modern day. If he does come to the Premier League it will be a big plus and a big plus for the team that he comes to.’
After joining Liverpool – who face Chelsea on Sunday – Thiago said: ‘It’s an amazing feeling. I was waiting for this moment for a long time and I am very happy to be here.
‘I must adapt to the team as fast as I can in the situation and the context that we are living right now.
‘Everything is more compact and we started a little bit later, but still it is football and I think we have to mix all the big things up, all the good things we have.
‘I will help the team in a defensive and offensive [way] and also in a mental aspect.’