Martin O’Neill has not given up hope of Celtic qualifying for the knockout stages of the Champions League, but concedes it is likely to be “some years” before a side from the Scottish Premier League makes it to a European final.
Following their 3-0 defeat by Shakhtar Donetsk, the Bhoys are currently bottom of Group F without a point from their opening three matches.
With a trip to Barcelona to come before a Parkhead date with AC Milan for their final fixture, O’Neill admits an “exceptionally difficult” task lies ahead.
However, the Ulsterman also feels the restrictions of the Scottish Premier League are continuing to have an impact on how teams do in Europe.
“Other teams have recovered from having no points on the board after three games and although I must admit with the likes of AC Milan and Barcelona in our group, life is exceptionally difficult,” said O’Neill on BBC Radio Five Live’s Sportsweek programme.
“We are a very big club and have a fantastic support, but are in an environment where we are unable to make some things pay.
“For instance, if provincial sides in the Premiership stay in the Premiership, I think they can look forward to something between £20-25m (€28.8m-€36m) of TV revenue.
“That is pretty substantial because we can look forward to round about £1.2m (€1.7m) per season and there hangs a phenomenal difference.
“We are certainly in a difficult situation, but the fact is the team have done magnificently, including in European football. I think it will be some years before an SPL team contests the final of any European competition.
“Celtic is a big club, but if you are not in the right environment, then you have very obviously difficulties ahead of you.”
O’Neill’s side are currently five points ahead of Old Firm rivals Rangers at the top of the table.
And despite becoming the dominant force in Scotland since he arrived four years ago, the former Leicester boss knows he faces a continuing drive for success.
He declared: “I am still enjoying the job immensely and get a phenomenal kick out of it.....But I don’t think that anybody can sit and rest on their laurels.”