Following a lacklustre first-half, Karim Ansari Fard's 63rd-minute goal lit up an otherwise dour Group D contest at Qatar Sports Club to seal a second consecutive triumph for Iran after their opening 2-1 win over neighbours Iraq.

"Our group was the 'group of death' and I still believe it is the most difficult group in the tournament. To achieve this result two games in a row, I'm very proud of my players," said Ghotbi.

"Iran are capable of playing much better football. We will show that in the coming games.

"We will be fitter and more confident and hopefully you'll see much better performances from our team.

"When we came to this tournament it was very important to try to get the job done in the first two matches so we could have a longer recovery time for our team.

"I was very satisfied because we had four changes in our team due to the flu and that shows that we have quality on the bench and we were able to sustain that level of performance.

"Any time you make changes, it takes time in the game to find the rhythm you need. The second factor was that when you play North Korea, you have to be patient.

"In the first half we didn't pass the ball with enough speed and it gives the North Koreans the opportunity to get numbers behind the ball.

"At half-time we talked about how important it was to stretch the game and close them down quicker and higher and that changed the tempo of the game."

The result leaves North Korea on the brink of elimination with just one point from two games in which they have failed to find the back of the net.

However, coach Jo Tong-sop insisted he would not change his side's counter-attacking style in pursuit of goals and the victory they need over Iraq in their final game to keep alive their hopes of qualifying for the last eight.

"Of course we have only one point, so the next match is very critical for our team to go for the knockout stage but we will try our best to win the match so that we can proceed to the next round," he said.

"In terms of the system, we converted to 4-4-2 and we combine attack and defence and in this way we created new tactics for our team.

"For the next match, I think we have to again put the emphasis on defence and try to score goals on the counter-attack."