Wednesday, so confident on the road last season, have sometimes being guilty of caving in at Hillsborough in recent seasons.
But now the Scottish midfielder knows that the remaining four games left at S6 must result in wins, starting with Preson North End on Saturday.
"Home advantage will be vital," he told Footymad. "When we get 24,000 at a home game, its different class and the crowd make a big difference. Hopefully they can carry on supporting us like they have done all season – it’s fantastic really.
"Especially at this stage of the season, points are more important that performances. I have been in a relegation battle before with Livingstone but we came out of it then and hopefully we can again this year."
Looking at the weekend though, Preson come to town bang in form but O'Brien is confident that if Wednesday play like they did against QPR, then the points should be theirs
"We have to take every game one at a time, it would be silly to take it any other way so we have to now concentrate on Preston and get three points from that game. If you look at the league table then they will be a sterner test that QPR so we will gladly take that challenge on. They are trying to cement a place in the play-offs but we keep playing as well as we did then I think we will be ok.
"We are playing well and creating chances, Southampton aside, but we are doing really well at the moment but I do believe that we will stay up and I think we will."