Dejected Kris Commons was at a loss to explain Celtic's Champions League flop against Ajax last night.
A win or a draw against the Dutch side would have put the Hoops in with a great chance of reaching the last 16, but after losing to Lasse Schone's second-half strike, Neil Lennon's side are sitting at the bottom of Group H.
After three promising displays in the opening group matches, Celtic barely competed with Ajax, with the narrow scoreline failing to reflect the gulf between the two teams.
"There are not many times we have come to one of these occasions and not performed at a proper level," Commons admitted. "Coming in 0-0 at half-time flattered us really because we didn't pass the ball well, we didn't look inventive.
"We had no imagination going forward and we were losing the ball too easily. We looked a little bit out of our depth.
"I think that's one of the first games where we really did lack belief going forward. The first half was probably one of the worst we have seen, attacking wise.
"Sometimes you can half accept it if it's in the SPFL the week after one of these Champions League nights, but for the lads who felt fresh and played Ajax two weeks ago and beat them, we lacked confidence going forward."
Celtic host AC Milan later this month knowing that they must win the match or face almost certain elimination from Europe with their final match away to Barcelona.
Lennon will have a job raising his players for that match with Commons well aware of the enormity of the task facing Celtic.
He believes some of his players departed the Amsterdam ArenA "with regrets".
The Scottish champions were far from their best in the crucial Group H encounter and were sunk by a 51st minute strike by Schone.
Lennon said: "We could have done better with the final ball and that has been a concern for the last few weeks.
"We missed some decent opportunities, particularly the James Forrest one when were two on one. When Schone scored, we were just getting a foothold in the game."