The Republic were repeatedly picked off as they threw caution to the wind, something they have rarely done during O'Neill's four-year reign.
"I thought there was an agreement".
He said: "That's simply not true". Everybody is entitled to a little bit of luck, so I totally disagree with you. "We were well beaten in the end". We were more effective than in Parken, the effectiveness is very important in football.
"He's absolutely in the top 10 (players in the world)".
Denmark's Christian Eriksen celebrates after the match against Republic of Ireland.
"He is one of the best players in the world but take that aside, as a guy and a person in the dressing room, he is a guy who can take the hopes of the nation on his shoulders and do magic with it". Christian is more a wide man or a central midfield player.
Eriksen, who has scored 21 times in 75 internationals, said there were more goals to come from Denmark in Russian Federation.
He said: "He's in a team now at Tottenham which wants to play football".
"It's incredible to take your country to the World Cup with three goals in a playoff", said 25-year-old Eriksen.
O'Neill will have a full strength squad to pick from tonight as none of their eight players who started the first leg on a yellow card received another one.
The Danes also benefitted from an Andreas Christensen goal, that cancelled out Shane Duffy's early header for Ireland, and a late Nicklas Bendtner penalty but Eriksen stole the show.
"We'll take this with us and try to score as many goals as possible at the World Cup as well", said the midfielder, who doused former worldwide defender Lars Jacobsen, who was broadcasting for Danish TV, with champagne as he celebrated. "That was the goal and aim before I started as the coach for Denmark and I am very pleased".
The defeat means that the Irish will not be going to the World Cup in the summer following a 0-0 draw in the first leg in Scandinavia. "It's a big thing and I'm very happy about it".
"It's an incredible feeling".
If we did need firing up for the game, however, then RTÉ Sport, as they often do in these situations, have provided the ideal tonic with an inspirational promo starring none other than Brendan Gleeson for the big game.