CELTIC are just a week away from stepping out in the San Siro to open their Champions League group stage campaign against AC Milan.

With the awesome figure of Group H favourites, Barcelona, also looming large on the horizon, the collective juices of players, management team and supporters are already flowing.

But the bookmakers have already decided that Celtic's main hope over the next four months of enthralling European endeavour will be to beat Ajax to third spot in the group, and collect the parachute placement into the last 32 of the Europa League.

Of course, given what they achieved last season, when they defied the odds to take a record 10 points and qualify for the last 16 of the Champions League alongside Barca, no-one at Parkhead is prepared to concede that finishing ahead of bottom spot is the best they can reasonably expect.

But, then again, being underestimated can be a powerful part of your armoury, the element of surprise a well-known and effective tactic when facing much bigger and stronger opposition.

New Bhoy, Derk Boerrigter, knows just how dangerous it can make any side, having watched his former club, Ajax, finish above mega-rich Manchester City in their group last season.

And the flying Dutchman reckons that, even though Frank de Boer's side were a surprise package themselves, they might still be susceptible to a little bit of a pincer movement by Celtic this time around.

He was a very interested spectator - sidelined through injury - when the Hoops lost 4-0 in the Amsterdam ArenA at the end of their pre-season tour last summer.

Boerrigter reckons that might just allow the Ajax guard to be subconsciously dropped when the sides meet again next month.

"The Ajax players who played in that game last year will still have in mind how easy it was to win the match," said the 26-year-old.

"So, perhaps they will underestimate Celtic when we meet again in the Champions League. But it was a friendly, there was nothing at stake.

"When there is something on the line, like in a Champions League game, it will be totally different."

Boerrigter is happy to be the spy in the camp for Celtic, and Neil Lennon is already availing himself of the detailed information the man who had two spells at Ajax has at his fingertips.

He helped Ajax win the Eredivisie last season before making the £2million move to Parkhead in search of more game time.

But Boerrigter acknowledges he left behind a very talented group of players.

And, with Christian Eriksen now having followed him out the exit door - he joined Spurs - Boerrigter had no hesitation in pin-pointing who he believes must now be considered Ajax's main danger man - if he is fit.

Siem de Jong has been out for a month after suffering a collapsed lung, and the initial estimate was the Dutch internationalist midfielder would be sidelined for six weeks.

He is about to find out if he is to be given the green light to resume training, but is not expected to make his club's opening group game in Spain next week.

If the man who scored 16 goals last season is back to face Celtic in their mid-group double-header, Boerrigter has warned his Hoops team-mates they must be wary of him.

"I don't know if Siem de Jong is fit at the moment, but he is a really good player," said Boerrigter.

"He is the captain and leads the team.

"Besides that, Siem is the one who can score from all kind of positions and distances.

"So we have to watch out for him in these games."

Boerrigter is keeping tabs on de Jong's rehab as he keeps in contact with several of his former team-mates.

And he is determined he will be claiming the bragging rights after the dust has settled on the group stage action.

Boerrigter accepts the draw could scarcely have been tougher, but retains a confidence which bodes well for the campaign.

"You always have to aim for the highest position in the group," is his positive approach.

"If that doesn't work out, then you try to become a good second or third."

He continued: "People have already said we are going to finish last in the group, so we are free to play. Last year, everyone thought Ajax would be last in the group which had Real Madrid, Manchester City and Dortumnd.

"But eventually we won and drew against City and left them behind us as we came third. Everyone here wants to remain in Europe, even if it is the Europa League."

When Ajax dropped into that competition back in February, they were tipped to go far, but crashed to Steaua Bucharest at the very first hurdle.

"I am really looking forward to the Champions League campaign," said Boerrigter. "We have been drawn against some really good teams.

"So, it will be very tough for Celtic to get out of the group. But it is not impossible. We just have to focus on every game and try to win them."