Dean Smith was unhappy at the manner of the goals Norwich City conceded in a 4-0 Premier League defeat to runaway leaders Man City.

Raheem Sterling’s hat-trick and a strike from Phil Foden ended the Canaries’ three match unbeaten run in emphatic fashion at Carrow Road.

Grant Hanley’s header struck a post with the game goalless but Sterling cashed in on a mistake from Max Aarons to open the floodgates for Pep Guardiola's side, who moved 12 points clear of nearest challengers Liverpool.

“A tough night. I am frustrated with the manner of the goals we conceded,” said Smith. “If we had lost 6-0 and Manchester City had opened us up with wonderful football and scored wonderful goals then I am probably more accepting of this defeat. Of course they had big chances but the manner of the goals we conceded is what disappointed me. We can’t legislate for mistakes, they happen.

“Max has made one for the first goal. But we stayed in the game. Teemu Pukki had a chance, worked the keeper, Kenny (McLean) had a good chance from the edge of the box and Grant has hit the post. But the moments were few and far between. They controlled possession really well. The second goal probably killed the game for me.

“It flattened the atmosphere, which I thought was brilliant in that first half. It was something we had spoken about at half-time. They like to drag your full back out and make that space in between and (Ilkay) Gundogan made that run.

“It took the wind out of our sails. We spoke about the third goal as well, defending the second phase of a set piece. That is why I am so annoyed we didn’t compete inside our box on a ball that travelled from outside our box.”

Sterling sealed his hat-trick from the penalty spot, after Hanley was adjudged to have fouled Liam Delap.

“It is never a penalty. I told Andre (Marriner) afterwards that is a pathetic decision,” said Smith. “It will probably get a tick on Mike Riley’s stats calendar but that has never been a penalty. He said he wouldn’t give it for a push, he wouldn’t give it for upper body contact.

“He gave it for lower body contact, where two lads have just run into each other. For me, a pathetic decision. It doesn’t seem to bother the officials when they give those decisions at 3-0 down. But it certainly hurts us.”

Adam Idah was a notable absentee after reporting soreness in his knee and ankle on Friday.

“We did a recovery day on Thursday, then Friday he came in and I can be honest it was after I had spoken to the media, but he had some ankle and knee problems,” confirmed Smith. “We thought it was too much of a risk so he has had a scan and we are awaiting the outcome of the results.”