BRENDAN RODGERS last night warned Celtic supporters that progress in Europe will become even more difficult for their team because of the vast financial gulf which is only going to get bigger.

The 3-0 defeat to Zenit St Petersburg, which ended the Scottish champions’ Europa League campaign, evoked perhaps the first real criticism of Rodgers since he joined the club in May 2016 given the meek way his side were defeated in Russia on Thursday night.

However, Rodgers made the point that while he remains hugely ambitious about what his Celtic side can achieve, the reality is that forces outwith anyone’s control count against even Scotland’s richest club competing with teams, such as Zenit, who have 10s of millions more to spend.

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The Celtic manager, when asked if it would become harder to come up against ever increasing budgets, said: “It will do. I think we have to keep fighting. That is important for us. We’ve had a lot of great memories this season, both in Europe in the Champions League and in the league but that’s because we have had great opportunities and in the main we take those opportunities. 

“On Thursday night, I felt it was an opportunity on the back of how well we played last week. But we have to keep creating the opportunities. We go away, we look at games, we ask how we can improve, and each year it gets more difficult. 

“Next year’s qualification for a Scottish team to get to the Champions League becomes even more difficult. But that’s the level we are at, so we just have to keep working.”

Celtic do seem to have hit a glass ceiling in terms of European improvement and as Rodgers said, it is not going to be easier for them next season.

The club are cash rich and one way to improve is to spend big in the summer; however, that is an unlikely path for them to go down after years of frugality.

And when asked how far away he is from making Celtic a team which can offer a better challenge in either the Champions League or Europa League, Rodgers said: “Listen, it’s very hard to say. It gets tougher each year. I suppose it’s managing expectancy, really. 

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“If any Scottish team qualifies for the Champions League, that’s a big achievement. Then you are going to then go in and you look at Bayern Munich winning 5-0 against Besitkas. 

“And we’re normally in with two teams at least of real, real quality. So, I think Champions League qualification is a big achievement for a Scottish team. If you can then either get into European football after that, in the Champions League ideally or into the Europa League, you would hope you could make the steps. 

“If you look at these games against Zenit, we were clearly much better than them last week but our consistency wasn’t so good, so you end up going out.

“Year on year you have to try to improve and we hope that if we can be in European football we can do that. But there is always going to be the balance, we are always going to have young players, that’s where we’re at really. 

“But it’s great to see them develop and flourish. We hope next year in Europe we can take more steps forward.”