Norwich City were left battered and bruised after slipping into the Premier League relegation zone following Tuesday's 2-1 defeat to champions Chelsea.

Diego Costa was clearly offside in lifting the Blues' winner over John Ruddy to settle a painful encounter that saw Alex Tettey go to hospital for a precautionary scan on a leg injury, Gary O'Neil need stitches for a gashed head and Robbie Brady lose two teeth in a sickening collision between the City duo.

Neil insists City must fight on ahead of Saturday's trip to relegation rivals Swansea after a controversial defeat.

'When you are down that bottom end those wee bits of fortune do not go your way,' said Neil. 'What I did do was made the referee aware at half-time that he had got it wrong, the lad was offside, but the guy has made an honest call. It happens. I won't lambast him for that. We are really frustrated.

'I have seen the Chelsea goal back on video. It is offside. You would expect the officials to get it right, it is disappointing they have not got it right, they will be disappointed but obviously the assistant calls it as he sees it. He is not two or three yards off, but he is a yard or so and it is on the assistant's side. It is not as if our players are on the other side (of Costa).'

Neil confirmed Tettey's hospital check-up after his first half exit.

'Alex Tettey is away for an X-ray on his leg. It is precautionary, we are not expecting it to be anything major,' said Neil. 'When he came off he was in pain and there was no clear signs of trauma so we need to make sure we cover the bases. Initially it started on his fibia but went down towards his ankle area. I am not going to say poor us or feel sorry for ourselves. Football is a contact sport, if Alex is not fit for Saturday someone else will play.

'Gary has a two inch gash in his head, which has been stitched up, and Robbie Brady has lost two teeth and chipped another one. Robbie took a short corner, which was probably the wrong decision and it then ends up with him colliding with Gary, one busts his head and the other his mouth but it won't stop them playing (at Swansea).'

Norwich had gone into the match without Steven Naismith, who scored a hat-trick in his last outing against Chelsea for previous club Everton. Neil confirmed afterwards he had left the Scottish international out as a precaution after adverse results in routine fitness tests by the club's sports science department over recent days, hinting the Scot's heavy workload had taken a toll after a bit-part role at previous club Everton.

'He was just carrying a slight niggle,' he said. 'His scores are down in the tests we do on the players so that suggests he is not well. He has not played three games in two years at Everton so obviously we have a huge game on Saturday and it would have been a huge risk to play him in this one and it wasn't one I was prepared to take.'

Neil admitted City were again culpable in their own downfall.

'It has probably been the story of our last few games if I am being honest,' he said. 'We probably had better opportunities than Leicester and lose. West Ham, we are two goals up and draw, Liverpool winning 3-1 and we manage to lose the game so I don't think when that is a continuous theme it boils down to luck. Quality shows and at times we miss opportunities we should take.

'Defensively for the first goal to let the left-back score a minute in when I have a back five and defensive midfielder in front of the ball is a source of frustration for us.'