Millie Sian, BBC Sport
Here are the key lines from his news conference:
Pedro Neto will not be back before the international break as the winger is still "a few weeks" away from being available. There is no clear timescale for his return and the plan is to assess his injury again after the break.
O'Neil said he would like to "add more" to his squad so that he has "direct replacements" to cover for injuries: "With Pedro missing, there's no one that can carry the ball in the same way that he does. So there are areas where I would like us to be slightly stronger, but we try to use substitutions in the best way we can."
On the penalty awarded to Newcastle last week: "Anthony Taylor is doing the Championship game this weekend, so that's three referees now that have been relegated off the back of refereeing for us."
He added: "I haven't received an apology and I don't want one because apologies don't help. So hopefully the level improves."
O'Neil is expecting a "tough game" against Sheffield United: "They have had injury issues and played a lot of different systems, so it's one where the players will need to be adaptable on the day for. They have been well in most of their games."
He added: "They will win football matches this season. I've seen enough in them. They've caused some problems for teams and they've got some good footballers. They got promoted from the Championship for a reason. They're a good side, and it will be a test against them."
He also praised Tommy Doyle who spent last season on loan at Sheffield United: "He brings something different to the midfield. His passing range, ability on the ball, delivery from set plays and his personality and energy. He had a tricky summer. He hurt his knee twice, didn't do too much training before he arrived here, so he had to get up to speed and he's just knuckled down."
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