It was like reliving the nightmare of numerous missed chances that have afflicted Norwich City's Premier League return – the spurned half-chances, fruitless penalty claims and catastrophic defensive lapses.

It was like reliving the nightmare of numerous missed chances that have afflicted Norwich City's Premier League return – the spurned half-chances, fruitless penalty claims and catastrophic defensive lapses.

Sunderland's crunch clash at Carrow Road was not the time for Alex Neil's mean to find themselves back in that uncomfortable place, but they just couldn't help themselves.

Now they have a fortnight to digest the consequences unfolding before their eyes, unable to affect the outcome.

'You're right, we can't keep failing to take these opportunities to take points off a rival – but to be fair, this was our last one,' said Gary O'Neil.

'We won a massive one against Newcastle and this performance wasn't massively different to that game. In fact, after 35 minutes it felt very much like the Newcastle game, where we just needed that breakthrough. It was coming. I was expecting us to get one.

'Maybe some individual mistakes cost us. Referring decisions possibly. I don't think there was a lot else in it. We were probably the better team – it feels stupid standing here saying it when you've lost 3-0, but after 40 minutes or whatever, I could see no other team winning it apart from us.

'And even second half we were banging on the door for ages, had one cleared off the line, hit the post, all sorts of penalty shouts.

'Things went against us, as sometimes they do. Unfortunately for us it's in a massive game and the reaction from everyone around us will be we're bang in trouble now and it's a disaster. We know how big it is.

'But if you look closely at the performance, it wasn't too different to the games we've won recently. The main issue was there were a couple of errors we had managed to wipe out recently, that crept back in.'

So was one of those errors the first-half penalty that really set Sunderland on their way?

'I haven't seen the penalty again and whether the defender (Andre Wisdom) has made a mistake with his challenge or the referee (Andre Marriner) has made a mistake, either way that's really changed the game for us,' added O'Neil. When he does see the incident back, you imagine he would back the former.

Certainly Timm Klose's absence at the back was hard to ignore – but given it was his header in first-half injury time that helped Norwich open the door against Newcastle, the reasons City missed their Swiss centre-back were too many and often to mention.

Ultimately Norwich have to adjust to that reality and quickly, now that it has been confirmed Klose's knee ligament damage suffered at Crystal Palace is expected to keep him out for the rest of the season.

'It's a big blow,' admitted O'Neil. 'We'd finally got a settled team, settled back four. He'd started to play really well.

'Injuries are just one of those things and the squad has to be big enough and strong enough to cope with it. This time we didn't cope with missing him, but we've got two weeks now to make sure we get it right at a very tough place to go, in Arsenal. But Swansea went there and won, so there's no reason why we can't.'

Conversely Sunderland's difference remains fit, in Jermain Defoe.

'I think we saw that, and their chances were more open than our because they were on the counter,' added O'Neil. 'We definitely had enough chances to win the game. The first goal was going to be massive.

'If it wasn't such a big game and you were just looking at the performance, it wouldn't have looked so bad – but in the magnifying glass that is the Premier League and the stage we're at, results are all that matter and it's a terrible result for us. We've got two weeks off now to dust ourselves down and go again.'

• Follow Michael Bailey on Twitter @michaeljbailey