Penrith coach John Lang delivered a warning to his team's premiership rivals after the Panthers ended Brisbane's 2003 National Rugby League season with a spirited comeback win in the fourth qualifying final at Penrith Football Stadium.

Underestimate the minor premiers at your peril.

Under-rated Penrith went into the playoffs with the second-worst defensive record of the eight finalists. With Newcastle's elimination, the Panthers now hold the unwanted distinction of having the most brittle defence of the six surviving teams.

But having watched his side pile on 24 unanswered points and keep the Broncos scoreless for the final 50 minutes of today's impressive 28-18 victory, even Lang admitted to being more convinced about the Panthers' title credentials.

"One thing we do know is we can score as many points as any other side in the competition," he said.

"So they're going to have to defend very well also."

The Panthers rallied from a 14-point deficit late in the first half to run out five-tries-to-three victors and earn next weekend off.

Under the complex McIntyre finals system, Penrith's success also allowed Canberra to live to fight another day and Lang, one of the gentlemen of the NRL, admitted to giving a thought to Raiders coach Matthew Elliott when the Panthers trailed 18-4 after 38 minutes.

But a try to Penrith interchange forward Ben Ross just before the break turned the match, leaving the home team behind by just eight points with a strong breeze at their backs in the second half.

"I was very confident at halftime that we could go on with it," Lang said.

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