But veteran playmaker Benji Marshall says they can't blame the referees and the side's contentious round three loss to Brisbane should they fall short of the top eight.

The NRL conceded they got it wrong when Tigers backrower Robbie Rochow was penalised for not standing square trying to charge down a field goal attempt in their 9-7 golden point loss to the Broncos back in March.

Referees boss Bernard Sutton's admission meant little after Jamayne Isaako booted the winning penalty goal and the Broncos earned an important two points.

As it stands, the eighth-placed Brisbane are four points ahead of the 10th placed Tigers.

Had the result been reversed, the Tigers would be equal with Brisbane on 20 points heading into their round 19 clash with ladder leaders South Sydney this weekend.

And it appears it will play a big role in determining the finals chances of both sides.

But Tigers five-eighth Marshall said they had no one but themselves to blame if they miss the finals for the seventh season in a row.

"We had our chances to win that game without that decision," Marshall said.

"We didn't play well enough that night anyway.

"It's easy to look back on the past and say 'we should have won this game, we should have done that'. But you can't change that."

Utility Josh Reynolds was on Tuesday ruled out for the rest of the season with a shoulder injury while back-rower Chris Lawrence is racing the clock to return this year because of a hamstring injury and broken hand, making their job more difficult.

But their upset win over St George Illawarra on the weekend will be fuelling belief they can make it back to the finals.

And with Tigers greats Marshall and Robbie Farah back at the club it could still come to fruition with a strong season finish.

"We want to see the fairytale but at the moment that might not be in our hands, we might be relying on other results," Marshall said.

"Unless we keep winning and playing well, that's going to be taken away."

Australian Associated Press