Apart from that chance, Stoke really struggled to give Iverson too much to think about and with three minutes remaining they went down to ten men.
This was after Harry Souttar received a straight red card after he brought down Alan Browne when he was through on goal.
"We should score, but we don't"
After the game, when providing his assessment, O'Neill said:
“It is frustrating,” he admitted.
"I thought in the first fifteen minutes we allowed ourselves to be nullified a little bit. I think both teams were playing in the same system was a factor in that.
"We had not switched the play a bit quicker, we did that and we looked a really good side but we didn’t do it enough.
"I thought between 15 minutes and half time we were excellent. We should score, but we don’t. We maybe picked the wrong pass or don’t get a cross or people in the box enough"
He continued: "I thought in the second half to be fair to Preston, they made it more difficult for us and we didn’t cause them enough problems in terms of the decisions that we made.
"We continued to play a little bit in front of them, we had to turn them around a little bit more and we brought Jacob (Brown) on to try and give us that ability to get in behind.
"We just got a little bit bogged down in the second half. We overcomplicated things a little bit and we got picked off at times on the counter-attack because we lost the ball in some bad areas that allowed them to play the ball forward.
"We gave away some free kicks on the edge of the box which mentally gave them a bit of belief and hope. We are disappointed to not have taken more from the game."
"I thought he did well"
This fixture marked Christian Norton's first start for the club after previously making three appearances from the bench and when speaking on the 19-year old's showing, O'Neill was impressed with what he saw.
"I am very pleased for him, I thought he did well. He showed what he is about. He has got good energy, got good pace. . He is a strong boy as well.
"I think you saw him and (Sepp) Van Den Berg have a good contest. A young centre back, a young striker playing against each other.
"It is a big step coming and playing in the Championship. The boy has only been at the club since this season and he has adapted well.
"He has only been at the club for six months and the step up to playing in the Championship without having a loan is a big jump for a young player."
"He was really good"
Sheffield United loanee Rhys Norrington-Davies was utilised slightly out of position with him slotting in the back three instead of playing in his regular position of left wing-back.
When commenting on how he felt the youngster coped with playing in a position he's not quite so used to, O'Neill said:
"He was really good. 20 years of age. Real aggression in terms of stepping into the game and he can only get better.
"He is a little bit smaller as a centre back, so he has got to gauge when he can step around people and possibly put the ownness on the centre forward to deal with the ball instead of getting too tight.
"But I thought in terms of what he gave us, we probably haven’t had that this season, particularly since Morgan Fox has been unavailable and he has stepped into the game really well.”
The former Northern Ireland manager added: "It is good because I think he can play left-back, he can play left wing-back and he can play left centre back in a back three, so there a lot of positives from that.”
"He sees the game really clearly"
Finally, this game not only marked Norton's first start for the club but it also was Dean Holden's first game as assistant manager of the Potters after his appointment in midweek.
When speaking on how he felt the former Bristol City manager got on alongside himself, O'Neill admitted that he was impressed with how Holden connected with his players.
"I thought he was really good, he sees the game really clearly and I felt that he gave us good information,” he said.
"He was very good with the players in the dressing room, pre and post the game. So I am disappointed for him because when you come to a club you want to try and get off and win your first game.
"I know what that was like when I came to the club away at Barnsley. You want to win that first game, so he will be disappointed that we didn’t find a way to win the game, but he has been a big plus this week".