The Starbeck outfit were beaten 5-1 at leaders Hallam on Saturday, seven days on from a 3-1 loss to North Ferriby which brought to an end their six-match winning streak.
That run of form saw the Rail cement their position in the play-off places and their manager is determined that they get back on track before the kind of doubts which could damage their hopes of a top-five finish start to materialise.
“Saturday is probably our biggest game of the season so far,” O’Connell told the Harrogate Advertiser.
“It’s really important that we get back to winning ways. Regardless of how we play, we need to find a way to grind out a result and get three points.
“We’ve come up against the two best teams in the division in the last couple of weeks, so there’s no panic after losing those games, but my concern is that losing becomes a habit, just like winning does.
“After two defeats on the spin, it can be hard sometimes to get back on track. If you lose three in a row then it is even harder still because doubts start to creep in.
“We can’t allow that to happen because we’ve been doing really well and playing some good football. We’ve worked so hard to get ourselves up challenging near the top of the league and we need to make sure that we continue to do so.”
Despite them serving up a fragile second-half performance lacking energy and intensity which saw them ship three unanswered goals at Hallam, O’Connell is backing his charges to bounce straight back this Saturday.
“We’ve told the lads that we need a reaction and I expect that we will get one,” he added.
“I know this group. I know their character and what they’re all about. We definitely have the quality to beat anyone in this division and the spirit is still there. What I saw at training on Tuesday night, that told me that their heads are in the right place.
“The lads were really disappointed after Saturday but we just have to put that behind us now.
“We played really poorly against Retford not so long ago, but they responded in the next game and we went on a run. I don’t see any reason why we can’t do exactly the same again now.”
Reflecting on where his side went wrong at Hallam, O’Connell continued: “Ultimately we didn’t defend our box well enough.
“The first half was okay. We should have come in at 1-1, but we gave away two goals then never came out the changing room after half-time.
"We gifted Hallam three sights of goal and they punished us on each occasion. You cannot afford to do that against a team with their quality."
Saturday’s fixture against 11th-placed Armthorpe gets underway at Station View at 3pm.