The NRL’s Integrity Unit is investigating “suspicious” betting activity following a plunge on Canterbury to defeat the Penrith Panthers this Thursday night.

At the start of the week, it emerged the four-time reigning premiers were planning to rest a host of star players, including co-captain Nathan Cleary.

WATCH THE VIDEO ABOVE: Integrity unit probes suspicious betting activity.

But before those reports surface, there was a huge betting plunge on the Bulldogs, which sparked the investigation. The Bulldogs, who opened as outsiders at $2.30, shortened to $1.60 favourites.

And on Tuesday, it was indeed confirmed that the Panthers had rested players en masse.

After successive golden-point defeats to Melbourne and Canberra left the Panthers needing a miracle to claim a top-four finis

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