The South Africans collected their first ever FIFA Under-17 World Cup point after a 1-1 draw in the Group E clash with the Koreans.
Ntseki says he was pleased with the team's efforts on the day, but concedes that they were to blame for Korea equalizsng through a penalty.
"It was like playing 180 minutes, especially towards the end of the match," he says.
"We started very well, and we got the penalty [in the 10th minute], which was our plan we had - to get an early goal. We got the early goal but we lacked the discipline because we were too excited after scoring.
"Naturally after conceding, a team tried to take advantage of the excitement of the opponents, which is exactly what Korea did.
"If you look at the time between the two goals, it shows that we did not do very well in defending after scoring, so I think that is where the problem was."
Despite having a numerical advantage for over 80 minutes of the match due to Ri Kuk Hyong being sent off in the NINth minute, Amajimbos were unable to penetrate the Korean defense.
Ntseki argues that the cause for this was due to their opponents doubling their efforts to make up for being one man down.
"If you're playing a team that has just got a red card, they always double their efforts and we saw that from Korea DPR.
"From our side, I think it was a mental thing because we thought maybe after we scored the goal and they got a red card, the match was already won.
"I think it's a lesson learnt for our team, and for the boys in particular, because if you look at it there was no need for us to give away that penalty.
"Our defending was very poor, we allowed them to play behind our defensive line, and it's very difficult to defend when facing your own goals, which is what happened with us giving away that penalty," he adds.
Ntseki also explains that he tried to implement wing-play due to Korea DPR's defensive tactics following their red card, but concedes it wasn't up to the required standard from his troops.
"We tried to work more on the width because we were fully aware that they were closing the central area, and we played to many high balls to try and catch them behind the defense.
"I think towards the end of the first half we then realised that they were playing too deep - the only space between the defensive line was that of the goalkeeper - so all the ball that we played long was a give-away.
"In the second half we tried to correct that and circulated the ball much quicker, but I think they were very disciplined and alert all the time, because they cut out all our penetrative passes and blocked our shots from outside the box.”
Amajimbos now sit in third place with one point in Group E, while Costa Rica and Russia both on four points ahead of them.
Their next and final group fixture is against Russia on Sunday, with Ntseki's side needing nothing less than three points to stand a chance of advancing to the next round of the World Cup fixtures.