INTER MILAN legend Sandro Mazzola is worried the San Siro giants are set to let history repeat itself and underestimate Celtic again...just like he did.

Roberto Mancini's side come to Glasgow on Thursday for a repeat of the 1967 European Cup Final - where Celtic famously became the first British side to lift the trophy.

Mazzola played and scored that day in Lisbon and is Inter's most famous former player, having won two European Cups and four Serie A titles with the club he spent his entire career with, before hanging up his boots in 1977 having collected 70 Italy caps.

He still goes to games and is friendly with former Manchester City boss Mancini.

But he isn't impressed with the current side and admits he's worried about the Europa League clash with Celtic which he thinks is too tough to call.

Mazzola said: "The problem with Inter at the moment is they have no great players. And it's difficult to win if you have no great players. They have quite a few players who are good, but they are not great. That is the difference.

"I know Roberto very well and he is a very good manager. But like I said, his problem is he has no-one great to work with. He has proved he is a fantastic manager before both in Italy and abroad and he will come good here again.

"But it will require new players. I respect him a great deal. I admired him as a player and as a manager. He needs time...and a big cheque book.

"Inter play football which is good, but they cannot seem to finish teams off. They have also struggled to defend properly.

"The problem now in Italy lies not just with Inter, but with all Italian clubs. They cannot buy the best players in the world. Look at Xherdan Shaqiri. Yes, he is a good player, but he comes from Bayern Munich. Do you really think a club like Bayern would sell their best players? Bayern keep their best players.

"I haven't watched Celtic recently, but I know about Scottish football and their footballers. They are physical and will attempt to win the tie by being stronger than Inter and that might very well work.

"They also have a great mentality which I love - they never give up. And they are very strong in Glasgow, but not so good away I think. I don't know about Ronny Deila at all.

"It's honestly 50/50. I couldn't name the winner just now. Of course normally I would always say Inter, but they are not playing well and with any confidence. And in my experience you don't underestimate the Scots."

Mazzola admits he still gets frustrated when he looks back at the most famous clash between the two clubs 48 years ago.

But he admitted the Hoops thoroughly deserved their 2-1 victory.

He recalled: "I have a lot of memories of that game because I think about it a lot! I tell you before the match, we stopped to watch them train and do you know what they did? They played a practice match against journalists, with hundreds of fans on the side of the pitch who were drinking and laughing. It was like a village festival!

"Our manager Helenio Herrera was the only person who had watched Celtic and he came back and told us we would win the game easily and we had beaten Real Madrid and Benfica in the previous Finals.

"I scored a penalty early on. We thought we would win by three or four goals. But Celtic reacted brilliantly and the speed of their forwards troubles us a lot.

"We undervalued Celtic and I hope Inter don't do that again this week. We spent the whole game defending. Jimmy Johnstone and Bobby Lennox gave me in particular a lot of problems. Celtic were deserved winners."