EFE AMBROSE believes this young Celtic side are about to play the biggest game of their fledgling careers in Lisbon this evening.

But the 24-year-old Nigerian predicts that's a title which could soon be surpassed – because he reckons this group of players can soar even higher together and possibly lay claim to becoming the best Celtic team of all time.

A Champions League last 16 place is up for grabs if the Hoops can defeat Benfica. And Ambrose reckons that will simply provide the launch pad for the side Neil Lennon has assembled.

He said: "The more you win, the more confident you are that you can play at this level.

"We never thought we would be able to get three points in Moscow or against Barcelona or play the way we did in the Nou Camp. Now we know we can do it and believe in ourselves and believe in the team that we can really do something in the Champions League.

"There is more to come. We are young and most of us are just starting, but I believe this team is going to be the best Celtic has ever seen."

That's a massive call from the big defender. But there is no doubt the potential of this group is only just beginning to be realised.

If Spartak fail to beat Barcelona in Moscow in the earlier kick-off tonight, a score draw for Ambrose and Co. would guarantee at least Europa League football after Christmas.

But it's victory they have set their sights on achieving, to carry them on to 10 points and push Barca all the way to finish top of the group.

That would add another £833,000 win bonus to the £2million they have already banked for seven points accrued, while a further £3m reward for progressing to the last 16 would also be on its way to the Parkhead coffers.

No matter what their fate when the Champions League action resumes in February, Celtic's participation and qualification would make this season's campaign worth well over £21m.

But Nigerian international Ambrose, who cost only £1.3m from Israeli club, FC Ashdod, is only counting on securing the points Celtic need.

"This is a very big night, but I'm young and believe there is even more ahead of me," said Ambrose, who was voted into the Champions League Team of the Week for his performance against Barca in the Nou Camp last month.

"Benfica will come at us because they know, really, that they have to win to be in contention for qualification.

"It's going to be a tough game for us. But we know what we have to do."