Speaking to the media, O'Neil said: "Mario's fine. It was a conversation, it was nothing more than that. The most important thing to come out of it is that we need to get the best out of everybody.
"Of course, the other night sparked the conversation, but it was an important conversation that had to be had. Myself and Mario have a good understanding now of how we move forward and what it looks like. We dealt with it earlier in the week, so the focus since that moment has been firmly on Ipswich.
"These things, sometimes they can be tough to deal with and sometimes you can come out of them in a good spot, and I feel like we have. I have a lot of respect for Mario and what he's still going to be able to do for us. When we get the best out of him on the pitch, his level is so high that he's still going to play a big part for us.
"He'll still be around that group of senior players that lead the team, but at this moment we feel it's best for Nelson to lead the group."