Celtic manager Martin O'Neill was 'delighted' with the Hoops' second-half performance in their 4-1 Europa League defeat by Benfica, insisting they can still qualify for the knockout stages

Martin O'Neill praised Celtic's second-half showing despite their 4-1 Europa League thrashing by Benfica, which left them with no points from six in the league phase.

Colombia forward Jhon Duran converted a spot-kick just five minutes into the match in Lisbon after Hoops defender Dane Murray brought him down, before doubling his tally in the 35th minute, following defender Alexander Bah's strike midway through the opening period.

Celtic pulled one back through Camilo Duran on 63 minutes before Benfica substitute Vangelis Pavlidis added a fourth with two minutes left on the clock.

Following a 3-1 home defeat to Hungarian side Ferencvaros in their opening Europa League fixture at Parkhead, manager O'Neill maintains the second-half display in Portugal has given him grounds for optimism.

Speaking to TNT Sports, he said: "We started quite well, we forced a corner early on, and just trying to get into the game, they got a goal. The last thing you want to do is concede so early on.

"And then at 2-0 we've got a great, great chance to make it 2-1 and within a few minutes they make it 3-0.

"We could have capitulated, but I thought the second-half performance was really terrific.

"It was a game of two halves. We created chance after chance, we should have scored more goals.

"And of course, you're going to leave yourself a bit open at the end.

"But I tell you, the second-half performance gives me what I would call the determination and I think we can still qualify.

"I know it's down to six games, but we want to qualify for this competition to get into the knockout stages. We can still do it."

O'Neill conceded that Benfica's second goal was preventable, with Bah left unmarked to side-foot home a cross from talented 20-year-old Argentinian Gianluca Prestianni, yet remained determined to focus on the brighter aspects of the performance.

"One of their goals is just a little dink across, and we're coming out instead of defending it properly, and that's really poor from our viewpoint," added O'Neill.

"You can't afford to do that. I don't think you can afford to do that in any game, never mind a game of this magnitude.

"But trying to pick up from that, the second half, as I said to you, we could have capitulated, it could have been all over.

"But we came roaring back, the substitutes did brilliantly and we could have scored a number of goals.

"Yes, I accept the fact that then, on the break, they could have scored themselves – as they did for the fourth goal.

"But overall, I'm really, really delighted with the second-half performance, and it's a shame that we conceded the three goals first of all."