MONEY talks - but at the top European level, it screams. In Celtic's case, in agony.

After watching his side crash out of Europe with a 3-0 defeat to AC Milan, Neil Lennon admitted the quality cash can buy was a huge barrier for his club.

And, while the Scottish champions continue to have to pre-qualify for the competition proper - this season they negotiated three rounds, which will be the case for the foreseeable future - the urge to plough vast amounts of money into the squad will be resisted.

The lack of a top-class striker has been evident throughout this difficult campaign, which now threatens to leave them with their lowest-ever points haul.

Lennon did not hide from the harsh reality after seeing his side have 10 attempts on target, for a return of no goals.

Asked if he needs a better quality of player to compete with the real big boys of Europe, he said: "I think that's been apparent over the course of the campaign.

"Look, realistically, getting into the Champions League was fantastic for us. When the draw was made, we knew how difficult it was going to be.

"We competed, we competed again tonight. But that quality at the top end of the pitch has caught up with us this season.

"Some of the players have covered themselves in glory and been fantastic through the campaign, but it's been mainly the defensive end of the pitch we're talking about here."

That was not the case against Milan, with defensive lapses allowing the Serie A side to equal the biggest winning margin by any team visiting Parkhead on European duty.

On a night when they could have retained a genuine interest in again reaching the last 16, Lennon knows where his side came up short.

He said: "We missed good chances. The Virgil van Dijk chance was a great one. At 1-1, the game could have gone either way.

"Then we've conceded again from a corner. That's the most disappointing aspect, along with the chances we've missed."

Lennon added: "The big moments in the game change the course of it. Milan took their chances when they came along.

"But we contributed to our own downfall because, when the opportunities came for Kayal, Mulgrew, Van Dijk and Forrest, we snatched at them.

"We will have to improve if we are going to look to the future and continue to compete in the Champions League.

"We have to improve the squad we have now and we have to improve our recruitment from this year."

The BT deal means there will be even more money available for the SPFL champions, who get into the group stage from 2015, but Lennon warned: "It's never a foregone conclusion you're going to be in the Champions League.

"We do have some money, and we want to spend it, preferably in the January window. But it's not as if we didn't try to spend it in the summer.

"We had three or four targets in mind, but they fell through. January is a difficult period to bring players in, but we need to do that with next summer and qualification play-offs in mind."