NRL investigates unusual betting plunge

The NRL has confirmed it is investigating an odd betting plunge on last Saturday's match between North Queensland and the Bulldogs at Dairy Farmers Stadium.

The Sydney Morning Herald reports considerable money was placed on the Cowboys to kick a penalty goal as the first scoring play - a normally low interest option.

The late money led to TAB Sportsbet closing the bet option hours before kick-off.

NRL spokesman John Brady confirmed to the Herald that an investigation was underway.

"We're looking into some betting activity and seeking information on any trends surrounding that," he said. "We're talking to some people about it, and we're open to receiving any further information that is around on it."

The option did not ultimately pay as North Queensland turned down a simple shot at goal in the second minute.

The Bulldogs were penalised for not releasing the tackled player, Grant Rovelli, just nine metres out from the posts.

The Cowboys elected to run the ball and Ty Williams scored out wide.

Other betting agencies followed Sportsbet's lead by closing the bet option.

The Bulldogs ultimately won the game 22-20 with a late flurry of tries.

Earlier this year major bets were placed on the high-flying Storm to win the wooden spoon hours before their shocking salary cap rort was exposed to Australia.

Last season there were also allegations of a betting stitch-up as the Cowboys were heavily backed to win by 13-plus against Sydney Roosters in the final round of play, and came from well behind to win 32-16.