After Friday night's worrying 36-6 last-round loss to Gold Coast, parlayed into South Sydney's record-smashing 60-8 demolition of Sydney Roosters, the logical conclusion is that Newcastle's season has taken a turn for the worse.

Their best-case scenario is now officially defunct because, inexplicably, they allowed it to slip through their fingers.

Instead of opening their finals campaign on the sanctuary of home turf, fortified by back-to-back wins, the Knights now face a road trip to ANZ Stadium to tackle the red-hot Rabbitohs in an elimination play-off.

Adding to the odds stacked belatedly against Newcastle, before their first first play-off appearance in seven years, back-rower Mitchell Barnett has been accused by Gold Coast utility Tyrone Peachey of directing a racial slur at him on Friday night, prompting an investigation by the NRL integrity unit.

Barnett has denied Peachey's allegation that he used the words "black c--t" and he is entitled to the presumption of innocence.

Regardless of the outcome of the NRL integrity unit's investigation, the issue will nonetheless consume time and energy that O'Brien, Barnett and Knights officials can scarcely afford to spare.

O'Brien, in his first season as a head coach, already has his work cut out for him this week.

Somehow he needs to convince his troops, after such a deflating defeat, that they are capable of rebounding in the space of a week and performing at the level required to beat one of the form teams in the competition in a do-or-die final.

O'Brien admitted after the loss to the Titans that his team's inconsistency, in particular when playing against sides below them on the ladder, remains a "huge concern". He had no doubt that the major problem was "between the ears."

O'Brien is unlikely to have encountered such a vexing dilemma during his stints as assistant coach with Melbourne and the Roosters, two clubs who have been so successful for so long that killer instinct is ingrained in their collective mentality.

In contrast, Newcastle's squad on Friday featured nine players who are yet to experience finals action, so their learning curve remains incomplete.

While O'Brien has continually reminded his men this season "if we look too far ahead, we run into the car in front of us", perhaps last week the mounting hype and anticipation about a possible home final proved impossible for some to ignore.

Maybe certain players were more focused on the result than the process.

With that in mind, it was intriguing to hear Souths coach Wayne Bennett's post-match media conference after his team slaughtered the Roosters.

The inner-city derby, of course, kicked off minutes after full-time in the Titans-Knights clash, so Bennett had ample opportunity to inform his players about the favourable result.

"I never told them what happened on the [Gold] Coast," Bennett said.

"Never said a word. That doesn't inspire teams. You think it does, but it doesn't.

"They came here with a game plan. They came here with a job to do, with a good attitude, so you just don't need any add-on stuff that you think is going to motivate them any more, because it invariably never works."

Bennett's record would suggest he has a fair idea what works and doesn't.

In contrast to the Knights, the game's longest-serving coach doesn't appear have a worry in the world as he heads into week one of the finals.