BRENDAN Rodgers last night insisted Celtic can still defeat Valencia and progress to the last 16 of the Europa League despite slumping to a painful 2-0 defeat in the first leg at Parkhead.

The Scottish champions will have an uphill task overcoming their impressive Spanish rivals next week after conceding goals to Denis Cheryshev in the first-half and Ruben Sobrino in the second.

However, Rodgers, who could have Olivier Ntcham and Kieran Tierney back for the game in the Mestalla on Thursday, refused to accept the double treble winners have no hope of going through.

The Northern Irishman believes if Celtic, who have never won in Spain, can take the lead away from home against their La Liga rivals it will give them an outside chance of pulling off a major upset.

“We go next week to Valencia for what will be a very difficult game,” he said. “But if we get the first goal it brings a different possibility for us.

“We will dust ourselves off and enter the game next week with the personality and belief we can get something from the game. If you take away the two mistakes there wasn’t a lot in the game. You have to have that belief at this level.

“We have good players and might have one or two back next week. We need to defend and concentrate and, like I say, if we get a goal it might set us up for a really good second leg.”

Rodgers admitted he was alarmed by the poor quality of Celtic’s passing and the number of unforced errors his men made against Marcelino’s team in the first leg last night.

“It is a concern,” he said. “At this level it is a concern. It is basic mistakes. And that is concentration. At this level you have to have full concentration and do the basics well.

“The crowd were fantastic for us. You have to have that personality at that level – if you make a mistake you go again.

“It was a disappointing game to lose considering we made a good start. We were bright, had a good intensity in our pressing and we circulated the ball well.

“At this level you have to concentrate and you can’t put pressure on ourselves. Tonight, we put pressure on ourselves.

“But we made too many mistakes. We weren’t creating that passing and it got away from us. When you present those chances to a team with that quality they can punish you. They are very organised, very compact. They did that just before half-time.”

Rodgers added: “It’s a disappointing performance in the end. When you make the number of mistakes we made with simple passes you become a wee bit safe. And that was the story of our game, really.

"It’s a big challenge for us, but if we get that first goal (next week) it maybe gives us hope in the tie.”

Celtic had two penalty claims waved away by Romanian match official Ovidiu Hategan - when James Forrest went down in the Valencia box in the first-half and when substitute Odsonne Edouard was barged in the second

“You’ll take them if you get them, but I can see why the referee didn’t give them,” he said. “I don’t think they were clear. You’d maybe get them in Scotland!”

Valencia boss Marcelino also refused to accept his side had secured their place in the next round of the competition. “It may have seemed easy, but it was still a difficult match," he said. "All credit to my players for their excellent work.

“The atmosphere was extraordinary, but we managed to dampen it down by playing a good game. The tie is not over but it would take a huge error from us now not to qualify for the next round.”