The full-time whistle at Windsor Park was met by jeers, which then turned to a loud round of applause. The frustration was directed towards the match officials who left the field of play after adding only two minutes onto the end of 90 minutes, and waved away late appeals for a penalty. The cheers, which soon drowned out the jeers, were for a young Northern Ireland side who had given everything and put Germany on the ropes in the closing stages of the 1-0 defeat in World Cup qualifying. Ultimately, it came down to small margins. What if Paddy McNair hadn't strayed offside in the build-up to Dan Ballard's disallowed effort? What if the ball had bounced over or wide from Nick Woltemade's shoulder, rather than into the net? What if Callum Marshall's chance had fallen on his stronger foot? What if Conor Bradley wasn't suspended and forced to miss the game in Belfast after a soft yellow card against Slovakia?

Those questions don't change the result on the night, but they were the difference as a Germany side far from their vintage best got the job done to take charge of Group A. "We're disappointed and it's a sore loss," O'Neill, who was taking charge of his 100th game, said after the defeat. "I thought in the first half we lacked a bit of belief with the ball. Germany forced their physicality on top of us, and it was difficult for us to get any rhythm in the game.

"The disallowed goal would have helped us at that point, but it was offside. We shouldn't be offside in that situation so that's an error on our part." O'Neill felt Woltemade's first-half winner was a "freak goal" but said his players should have defended the corner better. "It comes off the player's shoulder and ends up in our net.

"That was the disappointing thing. But in the second half we were terrific. We just couldn't force an equaliser in the end.

"It was a game that was going to be decided by something special or a bit of a freak goal - which is ultimately how it was decided." It is not the first time Northern Ireland's young players had matched Germany after a battling 60 minutes in Cologne before the hosts pulled clear with a quickfire double. The contrast this time was stark, as Northern Ireland piled the pressure on the German defence in an additional two minutes that ended all to quickly - a tally O'Neill described as "ridiculous".

O'Neill also said that Northern Ireland missed the energy and quality of the suspended Bradley at right-back, but was delighted with the performance of his players in the second half. Windsor Park was at its rip-roaring best on Monday to greet Germany and O'Neill said the home support "carried" his young squad as legs started to tire.

"We're at home, that's the biggest difference [to the reverse fixture].

"We're at home and we're chasing the game. We've put a huge amount into the game on Friday night [in a 2-0 win over Slovakia] and the crowd carried us tonight when we needed them to carry us.

"We were chasing the game, so we are always going to try and find a way to get an equaliser." Despite the loss, and his frustration, O'Neill still had time for a joke with a member of the German media. "Having looked at the stats, ironically Germany played more long balls than us in the game," he said.

For his part, Julian Nagelsmann, whose comments after the reverse fixture in Cologne prompted O'Neill's quip, was relieved to get through a "tough" game. "The second half was all about defending," Nagelsmann told BBC Sport. "As I said before the game it was a really tough opponent, a lot of long balls and they fight and we had to fight as well.

"It was a good step in the right direction to beat a team like Northern Ireland and to fight for second balls and be as tough as the opponent." Top spot in Group A is now a long shot given Germany have put their grasp on automatic qualification. But second place and a guaranteed play-off is still on the cards ahead of November's two qualifiers in Slovakia and home to bottom side Luxembourg. It may not be much consolation now, but a play-off as one of four Nations League group winners seems to be a more secure fall back given other results across Europe, if Northern Ireland were to miss out on the top two.

So, after battling but falling short against one of Europe's giants, this young Northern Ireland side may be down, but they are definitely not out.